WILLIAM T. 



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Copyright N°. 



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COPYRIGHT DEPOSIT. 



' B. BAIRD, ViCE-PReSIOENT 



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38 1V.., __., NEW YORK 

TELEPHONE: 5718 BARCLAY 
CABLE ADDRESS: CHAUNBAIR, NEW YORK 



CRUDE 
RUBBER 



Crude Rubber Consignments Solicited 

Washed and Broken Down (or Refined) Rubber 

a Specialty 




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CRUDE RUBBER 



AND 



Compounding Ingredients 



A TEXT-BOOK OF 
RUBBER MANUFACTURE 



By henry C. PEARSON 

Editor of The India Rubber World 

Author of " What I Saw in the Tropics," " Rubber 

Tires and all About Them," etc. 



SECOND EDITION 



NEW YORK 

The India Rubber Publishing Company 

1909 



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Copyright, i899, By Henry C. Pearson. 
Copyright, 1909, By Henry C. Pearson. 





LIBRARY cfCONGRESSl 
Two Copies Received | 



PREFACE. 

Since the first edition of this book appeared, ten years ago, 
the rubber business has grown notably. New wild sources of 
"rubber have been opened in various parts of the world, and 
grades of rubber heretofore unknown have come into use. Plan- 
tation rubber, previously a negligible factor, has taken its place as 
a regular and constantly increasing product. Guayule rubber is 
used by millions of pounds annually. Progress in the reclaiming of 
waste rubber of all sorts has been constant and of great magni- 
tude. The industry at large preserves the same general outline 
as of yore, with perhaps the single exception of the making of 
motor tires, which is a new development and to-day one of the 
great divisions of the rubber manufacture. Of new compounding 
ingredients there are many, of substitutes a great variety, and of 
processes, good and bad, thousands. In the revision of the book 
those of a real or a suggestive value have been utilized. The 
general plan of the book has not been altered. It remains 
a dictionary of compounding facts, an encyclopedia of rubber 
factory practice. It is for rubber factory use and bespeaks for 
itself the same favor that it found with the practical man when 
it first appeared. 

The superiority of such a collection over the most compre- 
hensive book of compounds doubtless will be apparent to the 
expert manufacturer, for this reason. When a manufacturer 
buys a set of compounds — and most of them are purchasable — 
he invariably acquires them not so much for use as for sugges- 
.tion and comparison. The descriptions, therefore, of a great 
majority of the ingredients used in all lines of rubber com- 
pounding, and scores with which he may be unfamiliar, will 
be so suggestive to the practical man that new sets of com- 
pounds will be secured, each partaking of the individuality of 
the expert, and bearing the impress of the line of work done 
in the factory to which he is attached, and wholly free from the 
taint of imitation or counterfeiting, which is the bane of the pur- 
chased secret. It is felt that another point of superiority over the 



4 PREFACE. 

mere compound book will be found in the fact that no private for- 
mulas are given, which might wound the feelings of the more 
conservative manufacturers. 

The higher level of prices for crude rubber which has pre- 
vailed for some years past has drawn the attention of manufac- 
turers to the pseudo gums — such, for instance, as Pontianak. A 
number of these are described in this volume, with the hope that, 
since their presence in the market depends largely upon the 
insistence with which rubber manufacturers demand them from 
importers or gatherers, many more may be made generally useful. 

In the compilation and revision of this book free use has been 
made of English, German, and French standard technical works, 
as well as of technical journals, such as The India Rubber World, 
The India-Rubber and Gutta^Percha Trades Journal, the Gummi- 
Zeitung, The Journal of the Society of Chemical Industry, and 
others. 

The author takes pleasure in acknowledging his indebted- 
ness for helpful suggestions to skilled manufacturers and super- 
intendents in both America and Europe, and to the following dis- 
tinguished writers on rubber topics : P. G. W. Typke, F.C.S. ; G. 
S. Jenman, Government Botanist and Superintendent, of the Bo- 
tanic Gardens, Demerara ; William Thompson, F.R.S.E. ; H. 
Grimshaw, F.C.S. ; W. Lascelles-Scott, F.R.M.S., M.S.C.I. ; 
Richard Gerner, M.E. ; Dr. C. Purcell Taylor, Thomas Bolas, 
F.C.S., F.I.C. ; Professor D. E. Hughes, F.R.S. ; Messrs. Hein- 
zerling and Pahl, Berlin; Granville H. Sharpe, F.C.S.; Carl Otto 
Weber, Ph.D. ; A. Camille, John H. Hart, F.L.S., Superintendent 
Botanic Gardens, Trinidad; Sir Daniel Morris, K.C.M.G., Com- 
missioner of the Imperial Agricultural Department for the West 
Indies ; the late Dr. Eugene F. A. Obach, F.I.C, F.C.S., M.E.E.E. ; 
Dr. Joseph Torrey, Dr. David Spence, Hubert L. Terry, F.I.C, 
and many others. 



CONTENTS. 



CHAPTER I. 

Physical Characteristics of Crude Rubber; Different Grades and 
the Sources of Supply; Para, Central, African, and East 
Indian Gums; Origin of Trade Names; Botanical Details; 
Coagulation ; Plantation Rubber ; Oxydases 7 

CHAPTER II. 

Some Little Known Rubbers and Bastard or Pseudo Gums; Possi- 
bility of Development of their Use in the Factory 41 

CHAPTER III. 

(i) Divisions in Rubber Manufacture and Primary Processes in 
Manipulating the Gum. (2) The Washing, Mixing, and Calen- 
dering of Rubber; Knowledge of Gathering Processes Essen- 
tial to Intelligent Manipulation in Manufacture 53 

CHAPTER IV. 

Vulcanizing Ingredients and Processes ; Sulphur, Antimony, Sul- 
phides, and Other Materials Used; Vulcanizing Pressures and 
Temperatures 65 

CHAPTER V. 

Fillers and Other Ingredients Used in Dry Mixing in Rubber 
Compounds ; Sources, Properties, and Uses of the Various 
Materials ; Unusual Ingredients 79 

CHAPTER VI. 

(i) Substitutes for India-rubber and Gutta-percha. (2) Substitutes 
for Hard Rubber and Gutta-percha. (3) Miscellaneous Sub- 
stitutes and Compounds; (4) Mineral Rubbers; (5) Puncture 
Fluids and Fillers; (6) Celluloid and Cellulose Products. 
History of Their Use, and Description of Their Properties 108 

5 



6 CONTENTS. 

CHAPTER VII. 
Reclaimed Rubber and Its Uses i43 

CHAPTER VIII. 

Resins, Balsams, Gums, Earth Waxes, and Gum-like Substances 

Used in Rubber Compoimding 151 

CHAPTER IX. 

Coloring Matters. Reds, Blacks, Yellows, Greens, Blues, and Other 

Colors in Hard and Soft Rubber 172 

CHAPTER X. 

Acids, Alkalies, and Their Derivatives Used in the Rubber Manu- 
facture 189 

CHAPTER XI. 

Vegetable, Mineral, and Animal Oils Used in Rubber Compounds 

and Solutions 207 

CHAPTER XII. 

Solvents Used in India-rubber Proofing and Cementing and in 
Commercial Cements; Their Origin, Properties and Methods 
of Use '. 222 

CHAPTER XIII. 

Miscellaneous Processes and Compounds for Use in the Rubber 
Factory ; Waterproofing Compounds ; Shower Proofing ; Deo- 
dorization ; Preserving Rubber Goods ; Shrinkage of Rubber 239 

CHAPTER XIV. 

Physical Tests and Methods of Analysis of Crude Rubber; Specific 
Gravity; Analysis of Vulcanized Rubber; Solubility and 
Permeability of Rubber ; Deterioration ; Torrey's Method 260 

CHAPTER XV. 

Gutta-percha: Its Sources, Properties, Manipulation, and Uses; 
Components of Gutta-percha ; Vulcanization ; Gutta-percha in 
Compounds ; Methods of Analysis 276 



CHAPTER I. 

GRADES OF CRUDE RUBBER, SOURCES OF SUPPLY, AND PHYSICAL 
CHARACTERISTICS. 

To an even greater degree than is true of other organic sub- 
stances, India-rubber is hard to define in scientific language. Its 
atomic structure is hard to express, and means little when ex- 
pressed. It is a hydrocarbon, with the approximate formula 
QoHie; but some oxygen is always present, which has led some 
to believe that oxygen is a necessary constituent. As a rule, how- 
ever, the presence of oxygen is considered injurious, or a sign 
of deterioration. Rubber is as readily attacked by oxygen as is 
iron, and is as surely destroyed. The formula QoHig is of too 
general a nature to be of value, since it covers rubbers of widely 
different physical properties, and even includes Gutta-percha, 
A more important chemical fact is that rubber is extremely 
resistant, being soluble only in carbon disulphide, carbon tetra- 
chloride and in the volatile oils, such as turpentine, ether, gaso- 
line and the like. 

The physical properties of rubber are softness, toughness, 
elasticity, impermeability, adhesion and electrical resistance. Its 
most characteristic, but not most important property, is that it can 
be repeatedly stretched to many times its length, returning each 
time to about its first dimensions. No other substance is at all 
comparable to rubber in this particular property, though one or 
more of the other properties are possessed in turn by many other 
substances. 

Rubber is derived chiefly from the milk or latex found in 
the bark of many trees, shrubs and vines, and to a certain extent 
also in the fruit, leaves, soft wood, or roots. The great families 
of the Euphorhiacece, in tropical America, and the Apocynacece, 
in tropical Africa, furnish most of the world's rubber. The 
ArtocarpecB, of Central America and the East Indies, have a cer- 
tain importance, and the Composites, Asclepiadacece and perhaps 
other vegetable families contribute a certain amount. Altogether 
there are some thousands of species of trees, vines, bushes, weeds, 



8 GRADES OF CRUDE RUBBER. 

roots, and tubers which contain rubber ; but one genus, the Hevea 
tree, of Brazil, and another genus, the Landolphia vine, of Africa 
— and we should add the Castilloa, an American genus — together 
furnish practically the whole of the world's rubber. The tropics 
hold a vast store of wild rubber; but transportation, in these 
regions, is so difficult, and the growth of rubber trees so rapid, 
that it is becoming easier to grow rubber in accessible places than 
to get it out of the deeper forests; with the added advantage 
that plantation rubber is better prepared than would generally 
be possible in the forest. 

The vegetable latex, from which rubber is derived, is most 
often white, but is sometimes red or yellow. That of several 
African vines is pink, and the best Gutta-percha latex is as red 
as blood. The latex is usually thick, like cream, though the solid 
matter contained may vary from 20 to 60 per cent. 

It has never been definitely settled whether the rubber 
exists as such in the latex, or whether it is developed by the pro- 
cess of coagulation. Some latexes curdle immediately and spon- 
taneously, like blood; others require the addition of chemicals or 
natural fermentation, like animal milk. In many cases the latex 
has never been made to coagulate. In some cases the latex is 
used as food, while in others it may be highly caustic or a deadly 
poison. When the milk of Hevea, the Mangabeira rubber tree, 
or Balata is drunk freely, it shows no tendency to coagulate in 
stomach, but is apparently digested. The albuminous substances, 
which all rubber milk contains, are certainly assimilated by the 
system, and the other components also seem to be utilized, or at 
least behave quite unlike rubber. 

Another substance developed out of the latex, along with 
the rubber, is commonly called resin. Some regard this as a 
broken-down, oxidized, perverted or "unripe" rubber. Other 
authorities maintain the existence of a series of resin-bearing 
tubes in the bark, independent of the system of milk tubes, but 
drawn out with the rubber milk by the same bark cuts. 

Rubber is composed of two substances or "principles," one of 
which, the adhesive principle, is easily soluble in ether, carbon 
disulphide, and the like ; while the other, the nervy or structural 
principle, is never really dissolved. The adhesive principle cor- 



SOURCES OF RUBBER. ,9 

responds roughly to starch, while the nervy principle corresponds 
to cellulose. The adhesive principle seems to vary directly with 
the resin content, without being quite identical with it. There 
seems to be nothing else in nature which even approximates the 
insoluble or nervy part of rubber. It is this which gives rubber 
its elasticity, and enables it to take up compound; hence it forms 
the basis of rubber valuation. The adhesive principle, quite 
useful in cements and "frictions," forms the basis of a great 
number of "rubberlikes," and is of much less value. 

The classification of the many rubber sources, which at first 
sight seems such a simple matter, becomes really a perplexing 
problem before one gets very far into it. The manufacturer must 
get certain results with his material, and he classes his rubbers 
according to the results which he has got from certain grades in 
the past. In buying from the brokers and importers, they must 
agree on some sort of classification. The only classification which 
the importer can usually form will be based on geographical 
origin. He knows where his different lots of rubber came from, 
and that it about all. 

Far away, at the other end of the line, the outfitters, who 
receive the rubber from the native gatherers, must agree with 
the natives on some sort of classification and gradation. The 
native gatherers, among themselves, must learn how to identify 
those particular trees and vines giving the rubber which sells 
best at the coast. Then comes the white man with his experiment 
stations and rubber plantations, demanding a scientific restate- 
ment of the v/hole case. The botanists come along, each work- 
ing without m.uch regard to the other, with the result that we 
have about as many scientific classifications as there are botanists. 
Then comes the man with the business instinct, who aims to bring 
order out of choas by getting the manufacturer in touch with the 
original gatherer, and to thus have one classification for all, based 
upon the simple principles of economics. 

In working out this economic classification, the idea is not to 
add something new to the existing overproduction of classifica- 
tions, but to recognize and reconcile the existing ones, saving out 
that which is common to all. From the standpoint of values, 
the rubber plantation has greatly simplified the problem. Care in 



lo GRADES OF CRUDE RUBBER. 

the preparation of the milk has brought South American tree 
rubber, African vine rubber, and Ceylon-grown rubbers very 
nearly to one common level of prices. Nevertheless, this 
price classification is not final, because tree rubber and vine 
rubber cannot be used for the same goods in the factory, and 
different kinds of trees or vines, or even different lots of rubber 
from the same tree or vine, will give different results in the fac- 
tory, or in the hands of the consumer. 

In the final analysis, it is evident that a common sense classi- 
fication, based upon vegetable origin, must inevitably prevail. 
This does not mean a scientific botanical classification, because 
the botanists are guided by insignificant details of flower, fruit or 
leaf, leading them to useless classifications. What is needed is 
a popular or quasi-botanical classification, such as has been 
extended to apple trees or grape vines. Left to their own devices, 
the botanists will catalogue a thousand species and varieties of 
apple trees, but this misleads nobody, because we all know what 
an apple tree is. This, however, does not apply to rubber sources. 

The flower-fruit-and-leaf scheme, necessary to a w^orldwide 
classification of the vegetable kingdom, becomes nearly useless as 
a standard of measurement, when applied to the needs of business 
in one small corner of the vegetable kingdom, such as the rubber 
sources. Far better than that would be to adopt the native classi- 
fications bodily, since the native is not buried in a pile of unim- 
portant detail, nor lost on the barren stretches of the botanist's 
"families" and "natural orders." The man in the woods is not 
interested in corollas, lobes and cell sections, but rather seizes 
upon some prominent feature, such as an edible fruit or a milky 
juice or, maybe, a large, copper-colored leaf, and gives the same 
name to all plants which possess this striking or important 
feature. For the needs of any one neighborhood or industry, the 
native classification is of greater value, and is often quite accurate. 
Some of the scientific botanists have acknowledged the power 
of close observation and accuracy of judgment of the natives in 
these matters. To them this kind of botany is even more of a 
specialty than the botanist's botany is to the botanist. The white 
man will always do well to learn all he can from the natives 
around him, because this knowledge will be of immediate use. 



SOURCES OF RUBBER. ii 

Vegetation always adapts itself to its surroundings, so that 
geographical and botanical classifications have much in common, 
ultimately tending to coincide. Still, in most cases, any par- 
ticular bit of forest will have in it a considerable number of very 
different plants. We are bound to keep in mind that American 
rubber comes from trees, while African rubber is derived almost 
wholly from vines. To a certain extent, too, each of the impor- 
tant vines has its own territory, though there is always over- 
lapping, and some species are very widespread. 

In the succeeding pages the leading kinds of rubber now on 
the market are described and classified according to commer- 
cial usage, while reference is made also to the geographical 
distribution of rubber. 

South America produces the best rubber in the world and 
the most of it. The Amazon valley, embracing hundreds of 
thousands of square miles of rubber-yielding forests in Brazil, 
Bolivia and Peru, is the center of the industry, the product 
being exported from the city of Para, whence the name "Para 
rubber." Two or more species of the Hevea produce this rub- 
ber, the best known being the Hevea Brasiliensis. This, by the 
way, is the tree now being cultivated extensively in the Far 
East — to which subject further attention will be given on 
another page. Peru and other portions of the rubber area 
also produce a rubber, lower in grade than Para, known as 
"Caucho," and in some markets as "Peruvian rubber." This 
is the product of a species of Castilloa. Another species, Castil- 
loa elastica, is the rubber tree of Nicaragua and other Central 
American states, which is also found in Ecuador, Venezuela, 
Colombia, and Mexico, and yields the rubber known as "Cen- 
trals." The Atlantic states of Brazil, south of Para, produce 
other rubber trees, from which come the grades known as 
"Mangabeira," "Pernambuco," "Ceara," and "Manicoba." 

Africa comes next to South America in the amount of 
rubber produced. "African" rubber is inferior to that obtained 
from South America, but through improved processes in 
gathering and curing, the various sorts are delivered in much 
better condition year by year. African rubber is found on 
both the east and west coasts and throughout the great basins 



12 GRADES OF CRUDE RUBBER. 

of the Congo and Niger rivers, in the Soudan region, and 
also on the island of Madagascar. The Landolphia, of which 
there are several species, is a giant vine or creeper, from the 
milk of which most of the African rubbers come. Recently, 
however, an increasing amount of African rubber has been 
gained from trees, particularly the Funtumia elastica, which yields 
"Lagos" rubber. 

The East Indies to-day furnish but little rubber. The first 
rubber exported from that part of the world came from Assam, 
the name of which province has attached itself to rubber from 
other regions as well. The native rubber tree of India is the 
Ficus elastica. The islands of Java and Borneo, and also Penang 
and other states in the Malay peninsula, and likewise French 
Indo-China, produce a certain amount of rubber, mostly from 
vines or creepers. 

Seaports, trading posts from which the first shipment is 
made, the name of a colony or country, or descriptive terms, as 
"thimbles" "buttons," "strips" — all or any of these may serve for 
names of different grades of crude rubber. A complete market 
report would indicate that there are a great number of different 
qualities of rubber, many coming from the same source. This, 
however, is not wholly true. Take, for instance, the Para grades : 
years ago any rubber coming from Brazil was called Para rubber. 
Later it was divided into "fine," "medium," and "coarse." Then 
the rubber from the islands in the lower Amazon became known 
as "Islands rubber," while that coming from further up stream 
was known as "Upriver," and these, too, were divided into fine, 
medium, and coarse. Now a dozen or more local names are 
applied to rubber from different localities, tributary to the Para 
market. At the same time, most of these rubbers sell at the same 
figures, grade for grade, with the exception of coarse. 

Something like this is true in the African rubber trade. For 
instance, a great number of local names are applied to the Congo 
rubber. The difference between "Equateur," "Kasai," and 
"Lopori" sorts may not be greater than between different lots 
from the same place. With a very few exceptions, the names 
which follow are those used commonly in the leading markets of 
the world : 



PARA RUBBER. 13 

PARA RUBBER. 

Rubber is classified at Para and Manaos into three grades, 
designated by the Portuguese words fina, entradna, and sernamby. 
These same grades in the United States are known as "fine," 
"medium," and "coarse," while in England they are classified 
as "fine," "entrefine," and "negroheads," the latter being 
divided to provide for a subgrade, "scrappy negroheads." 
The proportion of these grades exported through Para of late 
has been about 61 per cent, of fine, 11 per cent, of medium, and 
28 per cent, of coarse. 

Fine Para rubber comes in large bottles or balls and, 
when cut, shows a surface closely marked with lines corres- 
ponding to the number of layers of rubber milk added during 
the smoking process. These layers are easily separated and, 
when stretched, are very transparent. This rubber smells 
not unlike smoked bacon. 

Medium or Entrafine resembles "fine," but is not so well 
cured, curds and globules of milk not perfectly smoked being 
found between the layers. 

Coarse or Sernamby is made up of the residue, scraped 
daily from the collecting vessels, or from milk which has cur- 
dled before it could be smoked and made into "fine." This 
grade takes its name from the supposed appearance of the 
scraps to the mussel fish, called by the Portuguese sernamby. 
This rubber is known in England as "Negroheads" when in 
large chunks, more usual in the case of Upriver supplies. 

Besides this genral classification of Para rubber, other 
names are in use, derived from the localities of origin. 

Islands rubber is that produced on the island of Marajo, 
some 17,500 square miles in extent, and other islands in its 
vicinity in the delta of the Amazon, together with that from 
other parts of the state of Para, except the Xingu, Tocantins, 
and Tapajos rivers, which might well be called lower Amazon 
grades. The Islands "fine" and "medium" rubber is in the form 
of round or flat bottles, while the "coarse" or "sernamby" is 
in scraps massed into balls and round cakes, which gives 
the name "Negroheads" to this grade in the English market. 

Caviana rubber, named from the island that produces it, 



14 GRADES OF CRUDE RUBBER. 

is the highest grade of Islands, and is to-day marketed as a 
distinct sort. It has a smooth, close grain, and is much in 
demand for fine work. 

Cam ETA rubber is so called from the port of that name, on 
the Tocantins river. It is noted for the superior quality of its 
"sernamby" grade, the "fine" being the same as from the islands, 
but rarely seen. This rubber comes in the form of little cups 
pressed into large "negroheads." It is largely used for mechani- 
cals, and is also suited for white tubing and white toys. 

Itaituba rubber comes from the port of that name, at the 
head of steam navigation on the Tapajos river, which enters the 
Amazon at Santerem. Rubber from this river is distinguished 
for the rather gutty quality of the "fine" and "medium," and its 
stringy, dirty "sernamby." 

XiNGU rubber, from the Xingu river, is noted for the specially 
good cure of the "fine." 

Upriver rubber includes the product of the country border- 
ing the Amazon and its tributaries above Para, and that which 
comes from Peru and Bolivia through the large streams rising in 
those countries — such rivers are the Purus, Jurua, Javary, and 
Madeira. This rubber comes to market in biscuits and balls 
varying greatly in size and shape, a full average biscuit weighing 
about thirty pounds. The difference in price between Upriver 
and Islands rubber is due chiefly to the fact that the latter, being 
derived from more remote localities, shrinks less after arriving 
in market. Upriver rubber is marketed also under such local 
names as "Manaos," "Madeira," "Bolivian, "Purus," etc. 

Manaos rubber is named from the city which is the capital 
of Amazonas, 1,200 miles up the Amazon river, and the center 
of the rubber trade of district, exported from this port. 

Madeira rubber, named from a great river which joins the 
Amazon below Manaos, is of excellent quality and produced in 
large quantities. It has a finer and closer grain than any other 
Upriver rubber except the Bolivian. 

Purus rubber comes down the river Purus, the largest of 
the rubber-yielding tributaries of the Amazon, and is probably the 
choicest of all the Para grades. A certain amount of the output 
of the Purus comes from a region formerly belonging to Bolivia, 



PARA RUBBER. 15 

and was marketed as "Bolivian" rubber. That region has been 
acquired by Brazil, and organized into the Federal territory of 
the Acre, which continues to produce a large amount of rubber. 

Bolivian rubber is floated down the Beni and other rivers 
in Bolivia to the Madeira, and thence to the Amazon. It 
meets innumerable dententions from cataracts in the upper 
Madeira, on account of which it becomes somewhat dried 
before reaching market. It has the further advantage of 
being cured by a better, class of labor than is common in 
Brazil, of having a tougher fiber and of being cleaner than 
most Upriver rubber, for which reasons it brings higher 
prices than any other. 

Not all the rubber of the Para grades now comes down 
the Amazon. A certain amount of the Bolivian output is 
shipped overland to the Pacific, and some by river to southern 
Atlantic ports. 

Peruvian rubber, in "ball" and "slab," was formerly applied, 
in the English trade particularly, to the class of rubber which 
will be described under the heading "Caucho." In recent 
years, however, Peru has supplied considerable rubber of the 
same character as Para — being derived from the same tree 
and under the same methods — such rubber now forming 
nearly half the shipments from Peru. This rubber is exported 
from Iquitos down the Amazon, most of it going to Europe, 
where it also is sold as "Peruvian." In English market 
reports, therefore, are now quoted Peruvian fine and negro- 
heads (coarse), as well as ball and slab, and also "Peruvian 
weak." The latter is understood to be the product of the 
same tree as the best Peruvian Para, but on higher lands 
and somewhat different soil. To a large extent Peruvian fine 
rubber loses its identity between Iquitos and the consuming 
markets, and is classed merely as Para, [Described in earlier 
editions of this work as "Jebe" rubber, mentioned by writers 
who had applied to it local designations, at a time when trading 
in it had not become organized.] 

MoLLENDO rubber comes from southern Bolivia, being trans- 
ported by steamers across Lake Titicaca and by rail to Mol- 
lendo, a Peruvian port on the Pacific, and thence principally 



i6 GRADES OF CRUDE RUBBER. 

to England. It is prepared in biscuits and sheets and is mar- 
keted at a price between Upriver and Islands. 

Angostura rubber comes down the Orinoco in Venezeula.. 
from Cuidad Bolivar, which town formerly was known as 
Angostura. It is of the same grades as the Para sorts. Some 
of the same class of rubber finds its way into Brazil, at 
Manaos, where its identity is lost. 

Orinoco rubber is the same as "Angostura." 

Matto Grosso rubber is from the state of that name in the 
southwest of Brazil, and reaches the market partly through 
tributaries of the Amazon and partly through the Parana, 
which discharges into the river La Plata. It comes in "fine," 
"medium," and "coarse," but principally the latter, little of it 
reaching the market at present. 

Caucho^ which figures in all the markets of the Amazon 
region, and in statistics of Para rubber generally, is a distinct 
sort of rubber, inferior to Para, collected from a species of 
Castilloa instead of the Hevea trees. It is not cured by smoking 
but by the admixture with the milk of lime, potash or soap. 
The physical characteristics of Caucho, in the main, are the 
same as the Central American rubbers. The rubber of this 
sort exported by way of the Amazon formerly was obtained 
principally from Peru, but it has now been discovered through- 
out most of the rubber-producing regions of Brazil and Bolivia 
as well. Caucho figures very largely in the Para rubber 
trade, the exports in three recent calendar years averaging 
i8^ per cent, of the whole yearly shipment through Para. It 
comes to the market in three forms — "ball," "strip," and "sheet" 
(or slabs) — ranging in value in the order named. 

Caucho is the Spanish word for India-rubber in general. 
When this particular sort of rubber first began to be marketed, 
it was obtained only in Spanish-speaking regions, and on 
coming down to Para, where the commercial language is 
Portuguese, and being rubber of a distinct type, it not unnatur- 
ally became known commercially by the Spanish name, which 
really was a most convenient form of describing it, so as to 
avoid confusion in the trade. The commercial designation of 
rubber in Portuguese, in use at Para, is Borracha. 



CENTRAL RUBBERS. 17 

CENTRAL RUBBERS. 

Central American rubber, or "Centrals," includes that 
which is produced in all the states north of the Amazon 
valley, up to and including southern Mexico. It forms a dis- 
tinctive class, being the product of a tree not native elsewhere. 
The consumption of Centrals in the United States was larger 
once than of Para rubber, but the yield has declined gradually 
to small proportions. This rubber is in good demand for cer- 
tain uses, ranking in price below coarse Para. It has not the 
toughness or strength of fine Para, and possesses less elasticity. 
Centrals are classed usually as "sheet" and "scrap," besides 
which the terms "strip," "slab," "ball," and "sausage" are 
used. Greytown being a common shipping-point for Centrals, 
there is much confusion, one sort often getting substituted for 
another. Most of the yield of Costa Rica is exported through 
Nicaragua. The treatment of Centrals generally consists in 
mixing with the latex the juice of the "amole" vine, often in a 
hole in the ground, the product being "sheet" rubber. The rubber 
drippings which adhere to the bark of the tapped trees are 
peeled off when dry and called "scrap." The trade names 
below apply to the locality of origin, rather than indicating 
distinctions in quality. 

Nicaragua rubber includes more than the product of that 
republic. The real Nicaragua rubber is drier, as a rule, than 
other grades of Centrals. Nicaragua sheet comes to market in 
a less clean condition than formerly, and the scrap now brings 
a better price. 

Greytown scrap is the best grade of Nicaragua rubber. 

Guatemala rubber is inferior and unequal in quality. The 
best is whitish in color, and the lower grades black with a 
tarry appearance. It is said to be sometimes adulterated with 
cheap molasses. In curing, the rubber-gatherers pour the milk 
upon mats to dry, afterwards pulling off the product in sheets, 
pressing them together for shipment. 

Guayaquil strip, from Ecuador, is imported in two grades 
— good and ordinary. Like the Guatemala rubber, the best 
has a whitish appearance. The inferior sort is porous and filled 



i8 GRADES OF CRUDE RUBBER. 

with a fetid black liquid, which carries an almost indelible 
stain. 

Esmeralda rubber, which also comes from Ecuador, is 
classed as a "strip" and "sausage," the two grades coming to 
market in about equal quantities. 

Colombian is a pressed strip rubber, dark in color, some- 
times showing white when cut. It is graded "No. i" and "No. 
2." Some of the rubber from Colombia bears local designa- 
tions, besides varying in quality. These include: 

Cartagena, strip rubber, dark and tough, graded "No. i" 
and "No. 2," selling at less than "Colombian." It comes also 
in thin sheets, rough or "chewed" in appearance, and tarry or 
sticky. The production has decreased very much of late. 

Panama rubber, like that from Nicaragua, embraces a wide 
range of quality. The Pacific mail steamers bring together at 
Panama rubber from numerous ports, and confusion of grades 
is a result. What is marketed as "Panama" comes in "sheet" 
and "strip." 

Virgin or Virgen rubber comes from Colombia in "sheet," 
"strip," and "slab." It is a product of a different tree from the 
other "Centrals" described here, and is in demand for the hard 
rubber manufacture. 

Mexican rubber is of fair quality, but is received in con- 
stantly-decreasing quantities. The grades, listed in the order 
of their selling value, are "ball" (or scrap), "strip," and "slab." 

Tuxpam strip comes from the Mexican port of that name. 
Very little of it is received, and that not of uniform quality. 

Honduras strip is of a quality similar to the Mexican, but 
is little produced. 

West Indian rubber has a good reputation for quality. It 
is not produced on the islands, but comes from Venezuela and 
Central America, and the designation is simply a general trade 
name used in England. 

It is to be kept in mind that the information given thus far 
under the general heading of "Central rubbers" relates to the 
native forest supplies from the countries mentioned. The same 
tree is now being cultivated extensively, and the product, which is 



CENTRAL RUBBERS. 19 

beginning to be marketed, will be considered in another place 
in this book. 

The grades which follow, though not entitled geographic- 
ally to be included as "Centrals," are in fact so classed, on 
account of their quality. 

Mangabeira rubber is so called from the local name of the 
tree producing it, in some of the Atlantic states of Brazil, south 
of Para. It is an alum-cured rubber and comes in sheets 
which resemble slices of liver and are of a tawny red color. 
The thin sheet sells for more than the thick, as it is drier and 
better cured. Occasionally it comes in the form of balls. It 
is exported from Pernambuco, Bahia, Natal, and other points 
on the coast. 

Pernambuco is another name for Mangabeira rubber, 
derived from the principal state and port from which it is shipped. 

Santos rubber, from another port, is the same. 

Ceara. — The following paragraph appeared in this place in 
earlier editions of this work: "Ceara rubber comes from a 
small tree particularly abundant in the Brazilian state of Ceara 
and is marketed principally in England. The milk exudes from 
the tree and coagulates in the form of 'tears' which are 
gathered in scraps and balls. There are three grades, the 
lowest of which is dirty and difficult to use. Ceara rubber is 
deficient in elasticity and is hard to vulcanize. It is very dry 
and free from stickiness." Since this was written the rubber 
of the region referred to has received much attention, and the 
output has been greatly increased. This rubber has come to 
be known more generally by the local name of the tree, "Man- 
igoba," of which there are now recognized to be several dis- 
tinct species. One of these, found in the state of Bahia, is 
considered to yield a superior quality of rubber, which is 
marketed as "Jequie" and "Remanso," these being locality 
names. 

GuAYULE is a Mexican rubber of a distinctively new type 
which recently has come into use to a very large extent. It 
was merely referred to in the first edition of this work as 
^'Durango" rubber, and by other names, though at that time 
it had not been taken up by the trade. This rubber is obtained 



20 GRADES OF CRUDE RUBBER. 

from a shrub peculiar to the arid regions of northern Mexico 
and southern Texas — being practically the only rubber found 
in the United States — which differs from most rubber produc- 
ing plants in that it has no latex, the rubber being chiefly in 
the cells of the bark, a little in the wood, and none at all in the 
new shoots or leaves. The bark also contains balsam-like 
resins which are extracted with the rubber and are the cause 
of its softness and stickiness as compared with fine Para, for 
example. Generally the extraction of the rubber resolves itself 
into two processes : one purely mechanical and the other part- 
ly mechanical and partly chemical. Whatever process 
is used, however, results in the destruction of the plant, 
so that unless means are discovered for reproducing 
the growth, the practical extinction of the species seems 
assured. At this writing the exportation of guayule from 
Mexico amounts to about 1,000,000 pounds per month, 
the larger percentage going to the United States. To a cer- 
tain extent the shrub is exported to Europe and America for 
treatment by various processes, but this is not encouraged by 
the Mexican government. Botanically the plant is known as 
Partheniuni argentatum. "Guayule" may be pronounced wy-u-le. 

Rubber manufacturers were somewhat afraid of guayule 
when it first appeared on the market, because of its softness and 
its slow vulcanizing qualities. They have, however, by learning 
to use the rubber, overcome most apparent difficulties and find 
it available for a great many types of goods. For example, it 
makes an exceedingly strong hard rubber, although it must be 
combined with a better grade of rubber. It, however, gives a 
gloss to ebonite that makes very beautiful goods. In mechanical 
goods, and, indeed, in all soft rubber work, it needs the addition 
of ingredients that are of a drying nature. For this reason it 
works exceedingly well with the drier and harder types of 
reclaimed rubber, and with such intractable gums as Balata. For 
some months prior to this writing the rubber has been quoted in 
the market at about 30 per cent, of the price of Islands fine Para. 

The various extractors of Guayule rubber have done some 
really remarkable work in extracting the resin, and producing 
rubber that comes about as near to being resin-free as any on the 



AFRICAN RUBBER. 21 

market. For example, one company has produced Guayule con- 
taining only 1,06 percentage of resin, which is less really than 
in Upriver fine Para, which contains normally 1.3. This Guayule 
rubber is said also to he very transparent, and free from stickiness. 
At first blush is might be thought, because of the freedom from 
resin, that the rubber would be equal in quality with fine Para. 
That, however, does not by any means follow, as the absence of 
resin does not necessarily presuppose the toughened fiber, the 
lasting quality, or even the compounding possibilities that Para 
rubber possesses. It is, therefore, quite possible that an addi- 
tional toughening process is needed to bring deresinated Guayule 
up to the standard aimed at. That this can be done is not 
unlikely, but it must be along the lines that give to Para rubber 
its extraordinary toughened fiber. 

AFRICAN RUBBER. 

African rubbers, though comparatively late in becoming 
known, are produced now in quantities second only to the supply 
from the Amazon. As a class they are more adhesive and less 
elastic than Para rubbers, ranking with or below Para negroheads. 
They often contain a liberal percentage of impurities, and for a 
long time their disagreeable odor and intractable nature hindered 
their introduction. But advancing prices for Para grades and fear 
of their coming scarcity led manufacturers to experiment with 
African rubbers, until many uses were found for them. The re- 
sult has been a notable offset to the general upward tendency in 
price of the Para grades, although there are many purposes for 
which Africans never have been considered as competing with 
them. At the same time, the possibilities in the way of utilizing 
African sorts have not been exhausted, each year bringing out new 
uses. Besides, more intelligent supervision of the work of pre- 
paring rubber in Africa has led to a great improvement in some 
grades, as compared with the condition in which formerly they 
came to market. 

The African rubbers are obtained from giant creepers, of 
"which there is a score or more species on the continent and in 
the island of Madagascar, and also from several trees, the most 
important one of which, discovered first in the Gold Coast Colony, 



22 GRADES OF CRUDE RUBBER. 

is known now to be widely distributed. There is now also a con- 
siderable production of "root rubber," obtained from underground 
creepers and marketed as "Lower Congo thimbles," and also as 
"Benguela," according to the sources of production. The adultera- 
tion of African rubbers is not uncommon, being due to the dis- 
honesty, not only of the native gatherers, but doubtless also of 
some foreign traders on the coasts. But in most of the European 
colonies in Africa stringent regulations have been adopted to 
prevent such adulterations. On the Gold Coast the lumps of 
rubber brought to market by the natives were formerly cut into 
strips or buttons by machinery, before being exported. Latterly 
some of this work has been done in England, the rubber then 
being known as "Liverpool pressed." 

As a rule, African rubbers are obtained by the destruction of 
the trees or vines with the result that the total receipts from that 
continent are decreasing, despite higher prices than prevailed 
formerly. 

The milk of the Landolphia vines, the chief rubber producers 
of Africa, coagulates on exposure to the air, though in some locali- 
ties use is made of various astringents, boiling in water, and other 
methods to assist in preparing rubber. Even where these methods 
are used, a residue of the rubber sap is left to dry on the bark 
and in the earth, and is gathered in strings or scraps. The only 
treatment in some other places is the smearing of the milk upon the 
bare bodies of the natives, where it dries speedily in the sun, and is 
easily peeled ofiF. Where rubber trees exist the practice of sys- 
tematic tapping has been introduced, with a view to preserving 
the trees, and more scientific methods of coagulation are being 
tried. 

Ball is the classification of a large share of the African rub- 
bers, which comes in every size from three or four inches in 
diameter down to half an inch or less. "Small ball" of the several 
kinds differs from the "large ball" in size, and is also drier and 
afifords a smaller degree of shrinkage. 

Thimbles. — The natives, after gathering this rubber, cut it 
into cubes, about an inch square or less. Thimbles generally con- 
tain bark and sand, but very little moisture. 



AFRICAN RUBBER. 23 

Nuts. — Rubber thimbles from Ambriz are quoted sometimes 
in European markets as "Ambriz nuts." 

Lump rubber comes in large pieces, varying in size and of 
irregular shapes. When packed in casks the pieces often become 
massed together in transit. It is from the best of the lump rubber 
that the most desirable buttons and strips are made. 

Flake comes in lumps, livers, and soft irregular masses, and 
is valuable in the factory chiefly for frictions and for softening 
compounds. 

Paste is the same as "Flake." The Accra flake and Niger 
paste, which are the same in quality, are at the foot of the list, in 
respect to prices, the Niger being the cleaner. 

Strips are lump rubber that is sliced and pressed by 
machinery before it is offered to the trade. 

Buttons is a name applied to rubber similarly treated as in 
making strips, except that it is cut into small pieces, whereas strips 
have been marketed in every length up to ten feet. 

Biscuits is another name for "Buttons." 

Oysters is another name for "Buttons" or "Biscuits." 

Tongues. — Some rubber formerly came to market in long, 
narrow, tongue-shaped pieces. The same grades are now more 
frequently seen in the shape of large balls. 

Niggers are of various sorts and from different sources. 
These rubbers are ball-like in some cases, having the appearance 
of masses of stringy rubber pressed together between the hands 
and wound into compact masses. 

Twist rubber is not unlike "Niggers" in quality, but shows 
less shrinkage and differs in preparation and appearance. The 
string or strip-like pieces are wrapped about each other in order 
to give a twisted look to the balls. 

The list of rubber grades "which follows is based upon a 
geographical arrangement, beginning with the upper west coast 
of Africa : 

FRENCH west AFRICA. 

This is an extensive region, extending from the Atlantic 
eastward to the precincts of the Nile, from which in recent years 
a great amount of rubber has come to French markets, the various 



24 GRADES OF CRUDE RUBBER. 

grades being designated generally by local geographical names. 
The leading grades now marketed from this region are : 

Conakry Niggers. 

Soudan Niggers and Twists. 

Bassam Niggers and Lumps. 

Lahou Niggers. 

Gamhie "A," "A.M.," and "B." These last are of the "Nig- 
gers" type. 

GAMBIA (BRITISH). 

Gambia Niggers (No. i, No. 2, No. 3). — These are classified 
according to cleanliness, No. i and No. 2 being fairly clean, and 
No. 3 containing considerable soil. 

Bathurst. — Same as Gambia. 

SIERRA LEONE. 

Sierra Leone Tivists (No. i, No. 2, and rejections). — This is 
white and amber in color, of low shrinkage, and has bark and grit 
in it, but little moisture. 

Niggers (No. i, No. 2, No. 3) are quite moist. No. 2 and 
No. 3 contain considerable soil. 

Cake. — Fairly clean, but wet. It is both red and white, the 
former bringing the better price. 

Manoh Twists. — This comes in the shape of tightly wound 
cords of rubber and works soft. In color it is black or white, the 
black being the better. 

LIBERIA. 

Liberian. — This is graded as Lump, Hard Rake, and Soft. 
It cuts yellow, is very wet, and is often a soft pasty rubber. 

ASSINEE. 

What is known as Assinee is graded : as follows : Assinee- 
Silky, Grand Bassam, Attoaboa, Lahou, Bayin, Half Jack. It is 
like Old Calabar, only it comes in chunks three inches square, is 
wet, and cuts yellow. These names are chiefly used in the English 
market. 

GOLD COAST COLONY. 

Gold Coast. — This is chiefly lump from which Strips and But- 
tons are made. There are also Biscuits and Niggers (hard and 
soft). The Flake is wet and has a bad smell, but otherwise is 
quite clean. 



AFRICAN RUBBER. 25 

Accra. — The Accra lump furnishes Strips and Buttons and is 
graded "prime," "seconds," and "thirds." The lower grades are 
Flake and Paste. 

Cape Coast. — This is another lump from which Strips and 
Buttons are manufactured and has for lower grades Flake and 
Soft. 

Salt Pond. — This Lump is also used in Strips and Buttons, 
the lowest grade being Flake. 

Addah Niggers (graded as No. i and No, 2) is very similar 
to Sierra Leone, but generally in smaller balls. It is not an Accra 
rubber, nor are Quittah Niggers or Axim. As a matter of fact, 
the grades from these different ports differ little if any, and are 
sold most frequently under the head of "Accra" rubber, from the 
name of the principal town in the colony. 

TOGOLAND. 

Lomi (or Lome) Ball. — The best grade of this is a clean, firm 
rubber and is fairly dry. The lower grades are rarely seen. 

NIGERIA (including LAGOS). 

Lagos. — This lump is also turned into Buttons and Strips, 
while soft inferior lumps are sold without manufacturing, as low 
grades. It is very easily distinguished from Accra by its odor. 

Niger. — The chief grade is Paste, which has an acid smell and 
is a low grade pasty rubber, wet but clean. 

Old Calabar. — It is graded as Blue, Lump, and Niggers, and 
is very bad smelling. The best lump is undoubtedly used for strips 
and buttons. 

Benin Ball. — Is generally dirty and has a rotten, woody smell. 

CAMEROONS (OR KAMERUN). 

Cameroons. — The Ball is graded as large, mixed, and small ; 
the Ousters, which contain some fifty balls, as No. i and No. 2 ; 
and the Knuckly ball, which is a small dry ball. This rubber has 
a fairly strong smell. 

Batanga Ball ("B," "E"). — Same as Cameroons, Batanga 
being the name of a river and country in the Cameroons. 

FRENCH CONGO. 

French Congo Rubber is very similar to Cameroons, but the 
balls are larger. 

Gaboon is the best known flake and has for additional grades : 



26 GRADES OF CRUDE RUBBER. 

Lump, Large "O" Ball, and Small "O" Ball. The Flake is free 
from dirt and is soft. 

Mayumba is both Ball and Flake. Another grade known as 
Mixed is a combination of the two and is sold as second quality. 

Loango. — Ball. 

These are names of rubber stations on the coast. The natives 
boil rubber milk, adding the juices of vines, and, while the rubber 
is hardening, wind it into balls, weighing from one-fifth pound to 
three pounds. The best rubber is not boiled, the milk drying on 
the wrists of the natives, as they tap the rubber vines. At the 
coast the balls are cut, to detect any cheating, and washed and 
packed in casks for export. 

BELGIAN CONGO (FORMERLY CONGO FREE STATE). 

Congo rubber comes in the shape of Buttons, Balls (No. i 
and No. 2), Red Thimbles, and Black Thimbles. The Ball is 
similar to Cameroons, but tougher. The Dutch Congo Ball is the 
same as the Congo Ball, but is known as the best grade of that 
rubber. There is also the Congo (Kasai), Black Twist (graded 
as fine, mixed, and secondary), and Red Twist. The Strips are 
among the toughest of African rubbers and are dry, with a woody 
smell. 

From the Lower Congo comes also the Luvituku, which is a 
Red Ball rubber, and from the Upper Congo, the following: 

Upper Congo. — Ball, Red Ball, Twists, and Strips, all of 
which is good tough rubber. 

Uele. — Strips, usually heated and fermented and bad smell- 
ing; Cakes, wet, but clean. 

Sankuru. — Ball, very similar to Congo Ball. 

Lake Leopold. — Graded as Sausage and Ball. It does not 
differ from the foregoing enough to warrant special description. 

Equateur. — In the form of balls (small and mixed). It is 
dark, dry, and clean, but contains some fermented rubber, which 
smells badly. 

Lopori. — Graded as Ball (large and small), Strips, and 
Cakes. Some of the balls are fine and clean, while others contain 
fermented milk. Lopori also comes as Sausage. 

Bangui. — Comes in the form of strips, firm and tough. 



AFRICAN RUBBER. 27 

Bitssira. — Ball; a trifle softer than Lopori, but usually of 
excellent quality and dry. In use it develops a strong smell. 

Aruwimi. — Ball. This usually comes as large, firm balls, 
but on cutting them open much of the interior is found fermented. 

Mongalla. — In this the Ball is similar to Upper Congo Red 
Ball. It also comes in Strips, and is a good rubber. 

Some other designation of Upper Congo are Kasai, Katanga, 
Ikelemha, Loango, Isanga, and so on. 

Bumba. — Ball ; Buki — Ball ; Tava and Kwilu are all good 
Upper Congo grades that are not distinctive enough to dwell upon. 

Wamha. — This is a grade of Thimbles and is a good black 
rubber, with only ordinary shrinkage. 

ANGOLA, 

Benguela. — Graded as Sausage and Niggers, Of the latter, 
No. I is clean and tough, and No. 2 contains a large percentage 
of red leaf, 

Mossamedes is practically the same, from a neighboring port. 

Loanda. — In this the grades, which are Sausage and Nig- 
gers, are similar to Benguela, but not so dry. There are also 
Twists (red and black), 

Ambris. — Chiefly Thimbles or Nuts ; both are poor grades. 

Lately a tuberous root in parts of Angola has been found to 
produce some rubber. This plant has been described by the 
natives as "Ekanda," 

EAST AFRICA, 

Uganda rubber comes from British East Africa, It is a tree 
rubber, prepared in sheet form under modem methods, and 
arrives in good condition, 

Mozambique rubber is that coming from the port of Mozam- 
bique, from other ports in Portuguese East Africa, and perhaps 
from still other places in East Africa, It possesses some proper- 
ties in common with the Madagascar rubbers. The rate of 
shrinkage is less than in most African sorts, and good prices are 
obtained. In the Liverpool market, which is the best for Mozam- 
bique grades, quotations are made for Orange Ball No, i. Ball 
No, 2, Ball No. 3, Liver, Sausage, Root, Sticks or spindles, Sticks 
removed. Unripe. 



28 GRADES OF CRUDE RUBBER. 

The Orange Ball (resembling an orange in size and shape) 
is the choicest rubber. Other grades of Mozambique Ball are 
distinguished further as "white" and "red," the latter being 
inferior. Its reddish color is due to the fine bark mixed with it. 
The Unripe contains more bark than rubber, and is not thoroughly 
cured. 

Sticks or spindles consist of spindle-shaped pieces made of 
slender strings of rubber wound around a bit of wood. Liver 
(or cakes) is in smooth pieces of irregular size. 

Lamu Ball, Liver, Sausage, and Root come from the Mozam- 
bique port of this name. They are not rubbers of a distinctive sort. 

MADAGASCAR. 

Madagascar rubber formerly ranked higher in price than 
most other African sorts, though to-day the highest price is ob- 
tained for some of the Congo sorts. Considering the greater loss 
sustained in washing, it costs nearly as much at times as fine 
Para. It is a favorite with manufacturers of hard rubber, on 
account of the fine lustrous polish which it assumes under the 
buffing-wheel. The principal classification is between Pinky and 
Black. 

Pinky comes in round balls, weighing i^ to 4 pounds, black 
on the outside from exposure to the air, but having a pinkish- 
white look when cut. 

Black, also in small balls, when cut shows a dark color, and 
is more or less sandy and dirty. 

Tamatave being the principal seaport, its name is liable to be 
applied to any grades shipped from there. But what is described 
as "Prime pinky Tamatave" is the best Madagascar rubber. 

Majunga rubber, from the west coast town of that name, is a 
dark rubber of special excellence, ranking next to Pinky in price. 

Niggers (or negroheads) are designated as "East coast" and 
"West coast," and also as "Red ball," and "Gristly." They gener- 
ally contain sand and dirt. 

Brown cure (or brown slab) is a still lower grade. 

Unripe is the lowest. This term is applied to balls containing 
bark in the center. 

Rubber from Madagascar is sold at French auctions also as 



EAST INDIAN RUBBER. 29 

"Lombiro," the native name of a newly found plant, "Morondava," 
"Barabarja" (names of localities), and so on. 

Madagascar rubber is cured ( i ) by the use of salt water, in 
which case the water is never wholly expelled, leading to a heavy 
rate of shrinkage, and (2) by artificial heat. The island is rich 
in rubber forests, but the exports are restricted by the wasteful 
methods of the natives, which exhaust the trees and vines, par- 
ticularly near the coast. 

EAST INDIAN RUBBER. 

Assam rubber is strong and of firm texture. It is fairly 
elastic, though often less so on account of carelessness in gather- 
ing and the introduction of impurities. There are four grades 
usually (No. i to No. 4), of which the lower ones are extremely 
dirty and contain soft rubber. The better grades when cut have 
a glossy, marbleized appearance, somewhat pinkish in color. 
Assam rubber is marketed in small balls, made by winding up 
strings of rubber dried on the trees, and also in oblong slabs of 
irregular size, wrapped in plaited straw. The output has declined 
for several years. Meanwhile the same species has been found in 
Burma, where the production of rubber has increased, though 
the whole output of forest rubber from British India is now 
smaller than at an earlier period. 

Rangoon rubber is the product of Burma, exported through 
the port of Rangoon, and differs so little from Assam rubber as 
to require no separate description. Four grades are marketed, at 
practically the same prices as for Assam rubber. 

Java rubber, from the island of this name, is dark and glossy, 
of a deeper tint than the Assam sorts, with occasional red streaks. 
Otherwise, its history and characteristics are nearly identical with 
those of Assam rubber. Three grades are recognized. The milk 
dries on the surface of the trees, on exposure to the air, and the 
shrinkage of the better grades is slight. 

Penang rubber (from one of the states in the Malay penin- 
sula, including the island of Penang) is also very similar to that 
from Assam. There are three or four grades, at slightly lower 
prices than the Assam sorts bring. 

Borneo rubber ranks below the other Asiatic sorts, being 
lower in price, with a higher rate of shrinkage. It is of a whitish 



30 GRADES OF CRUDE RUBBER. 

color, changing with age to a dull pink or red. It comes to mar- 
ket shaped like pieces of liver, and is soft, porous, or spongy. 
The pores are filled with salt water or whey, for the reason that 
salt is used to coagulate the rubber, and the water evaporating 
leaves a saline incrustation in the cells. There are three grades, 
the first of which is a good rubber, while the lowest, when cut, 
is almost as soft as putty, and is worth little. 

GuTTA-susu is a local name applied in Borneo to what is 
known in the markets at "Borneo No. 3." 

PLANTATION RUBBER. 

In the first edition of this work two lines seemed enough 
to devote to plantation rubber, since so little had then appeared 
in the market. In fact, with the exception of a few scientists 
and a smaller number of enthusiastic planters, no one then seemed 
to regard rubber cultivation as a practical proposition, and the 
rubber manufacturers were not the least prejudiced against 
undertakings in this line. The change which has come about in 
relation to rubber culture, influenced by the continued growth of 
the demand for rubber, while the extinction of the native supply 
in many regions seems assured, is indicated by the export of so 
much rubber already from Ceylon, where there is no native rubber 
— the product of a Hevea species introduced from the Amazon 
region. It was long supposed that the Hevea would not thrive 
away from the Amazon, but the success noted in Ceylon has been 
duplicated elsewhere, notably in the Federated Malay States, and 
Hevea species are now being placed under cultivation on every 
continent. The exportation of cultivated rubber from Ceylon and 
Malaya has increased at the rate shown by this table, the figures 
indicating weight in pounds : 

1903 1904 1905 1906 1907 1908 

Ceylon 41,684 72,040 168,247 327,024 556,080 912,125 

Malaya 1,000 13,000 228,800 817,769 2,089,085 3,671,435 

Total 42,684 85,040 397.047 1,144,793 2,645,165 4.5^3,560 

This rate of growth has been most encouraging to the 
planters, and large estates have been formed with the help of 
European capital and are being conducted by companies 
organized on the lines which long have proved so successful in 



PLANTATION RUBBER. 



31 



tea culture in Ceylon. It was estimated at the beginning af 1909 
that 300,000 acres had been planted to rubber (mostly Hevea) in 
Ceylon and Malaya, representing $75,000,000 of capital. The 
rate of production at that time was such as to lend support to the 
prediction that when the millions of trees not already producing 
should reach a tapable size the regions mentioned would alone 
be in a position to supply as much rubber as now enters into the 
world's total consumption. Para {Hevea) rubber has been 
planted also in India and the islands of Java, Sumatra, and 
Borneo, and other varieties to a large extent in Mexico and 
Central Amercia (mostly Castilloa elasticd), in several colonies 
in Africa (chiefly Manihot, otherwise "Manitoba"), and particu- 
larly in the Congo Free State (Landolphia vines and Funtumia 
trees). Rubber is being planted likewise in Hawaii and the 
Philippines, in southern Brazil, New Guinea, and elsewhere. 

Any fear of overproduction of rubber, through the coming 
into "bearing" of so many planted trees, is offset by the fact that 
thus far the sources of wild or forest rubber, with the sole excep- 
tion of the native Hevea (Para) trees in Brazil, are being 
exhausted by the extraction of their product. Where trees and 
vines are killed by the rubber gatherers, there may be an in- 
creased yield from a given country for awhile, due to the working 
of new areas from time to time, but ultimately the principal 
forests are overrun, after which the output falls ofif. A diagram 
is introduced to show how the export of Colombian rubber grew 



POUNDS ||si|ii|iii||||ii|£S|i£Sg§i§|i.Mgiiii'2ii,sisi|| 


7.000.000 -r- -r-^ ■' ^ r^ ~ ^~ - - 












4.W.0CO _- ^^"/T ' • ^ "^"v^ri 


■^^ - -- -_ ^^.-^_ ---- c^" --""- ^. - ' --^ 










«^ >^___^^Z -__ilf::_U __^:"-^__ 





32 GRADES OF CRUDE RUBBER. 

rapidly until it reached a high figure, after which it declined as 
rapidly to the low figure which has since prevailed. The same 
result has been seen in many other countries, and to-day the 
total output of African rubber is less than formerly for the same 
reason as in Colombia, while native rubber has almost disappeared 
in Assam. 

It would seem that manufacturers ultimately will be forced 
to adopt plantation rubber to a large extent. Thus far their 
opportunities for experimenting with plantation products have 
been confined chiefly to Hevea rubber from Ceylon and the 
adjacent states, and this has come into widespread use, having 
been adopted by most manufacturers. The cleanliness of planta- 
tion as compared with forest rubber has been an attraction from 
the beginning, and the higher price paid for the former has been 
due to its greater content, bulk for bulk, of rubber. But it has 
proved deficient in strength as compared with the Brazilian prod- 
uct. For some purposes the deficiency of nerve of the new rubber 
has not proved a disadvantage, as for instance in solution making, 
in which it has been used largely. Gradually it has replaced 
Para in many other applications, but as yet not for cut sheet, 
thread, and elastic bands. 

Rubber from Hevea plantations was at first clearly not 
identical with the product of the same species under forest condi- 
tions. The question was discussed whether this difference was 
due to the plantation rubber not being smoked, as is done with 
Brazilian rubber. A reason now more generally admitted is that, 
owing to the tapping of planted trees having been begun at a 
very early age, the product was "immature." At least plantation 
rubber can now be had with more strength than formerly, which 
may be due either to increased age of the trees or to better 
methods of collection, coagulation, and care in subsequent storage 
and shipment. 

Plantation or Plantation Para is the term applied in 
the trade to the new class of rubber. "Ceylon," "Malaya," or 
"Straits" are also applied, but these are merely local designations, 
indicating no difference in quality. What is more important is 
the growing practice of planters of stamping their product with 
trade marks, by means of which buyers may know absolutely 



PLANTATION RUBBER. 33 

the source of any particular purchase, which is helpful when a 
producer of several tons in a year is attempting to establish a 
reputation for quality. The number of such marks is too great 
for them to be enumerated here. Plantation Para is marketed 
in various forms, as follows: 

Biscuits. — Prepared by allowing the rubber milk to set in 
shallow receptacles, with or without acetic acid, and washing 
and rolling the cake of rubber which appears at the top more or 
less circular in form — usually 1/16 to 1/8 inch in thickness and 
10 to 14 inches in diameter. 

Sheets. — Formed in the same way as Biscuits, but rectangu- 
lar in outline. On account of their shape they lend themselves 
to more economic packing. Biscuits and Sheets are sometimes 
pressed together to form blocks. 

Crepe. — This rubber, on account of the washing and tearing 
which it undergoes between the rollers of the washing machine 
used in its preparation, contains a minimum of impurities. It has 
an irregular surface, is uneven in thickness, and, like Lace or 
Flake rubber, dries rapidly. On account of the washing which 
some manufacturers subject all rubber to, it has been questioned 
whether the extra labor involved in its preparation will be paid 
for by the extra price realized. Prepared in lengths of 3 to 6 
feet, and widths of 5 to 12 inches, and graded according to color. 

Worms. — The product obtained by cutting irregular sheets 
of freshly coagulated rubber into thin worm-like rods, shears or 
machinery being used. By passing the dry Worms through 
ordinary washing rollers they are bound together into an even 
strip of Crepe. 

Lace. — ^Very thin perforated sheets of considerable lengths. 
It comes from the machine in a continuous strip, and is cut into 
pieces 6 feet long as it runs on to wire trays. It is sometimes 
pressed later into Biscuits or Sheets. 

Flake. — Obtained by placing small pieces of freshly coagu- 
lated rubber in a small rolling machine or washer, the corruga- 
tions of which run horizontally ; the rollers are close together and 
the cut rubber issues as thin strips. 

Block. — Made from pressing together Sheets, Biscuits, or 
other forms of rubber, in a freshly coagulated or partly dry 



34 GRADES OF CRUDE RUBBER. 

state, in sizes usually lo x lo x 6 inches, the chief purpose being 
to reduce to a minimum the surface exposed to the air after 
preparation. 

Scrap. — The remnants obtained after tapping, rolled into 
balls or made up into cakes. It is shipped with or without other 
preparation; it is sometimes made into Crepe. It brings a com- 
paratively high price. 

The popularity of the various forms here described may be 
indicated by these statistics of the offerings of Ceylon and Malaya 
plantation rubber at the London auction of December 31, 1908: 
Crepe, 877 packages; sheets, 202; block, 128; biscuits, 59; worm, 
12; scrap, 35; total, 1,313. 

The color of Plantation Para is also taken into account. In 
England paleness is considered important, pale and clear rubber, 
or even amber color, selling best, 

Rambong is the native name in the Far East for the tree 
Ficus elastica, which produces the Assam rubber of commerce. 
A considerable amount of cultivated Ficus rubber, from Java, 
Ceylon, etc., is sold under this name. This comes in Crepe, 
Sheet, and Block. 

Manicoba plantation, and Ceara plantation are the product 
of the cultivation, in southern Brazil, of the various species of 
Manihot mentioned already under the heading "Ceara rubber." 

Ceara plantation, from the same species, comes from Cey- 
lon and Malaya, and from some German colonies in Africa. 

Mexican plantation, as this book is issued, is coming into 
market in increasing quantities, some of it very clean, and not 
differing otherwise in quality from the product of the same tree 
(Castilloa) under forest conditions. The higher price of this 
grade, as in the case of other plantation rubbers, is due to the 
smaller percentage of shrinkage. Mexican plantation rubber 
comes as Strips, when the latex is creamed, coagulated, and run 
between rolls, and as Grena when the product is scrap-picked 
from the cuts on the trees and coagulated only by exposure to 
the air. 

Trinidad plantation, Tobago plantation, West Indies Planta- 
tion Central American plantation, Guayaquil "Castilloa," and 
such terms relate to the product of cultivated Castilloa trees in 



COAGULATION. 35 

the regions indicated. A certain amount of Castilloa plantation 
rubber comes from Ceylon, 

Congo plantation, from various species, comes from Belgian 
Congo (Congo Free State). 

Uganda plantation comes from British East Africa. 

COAGULATION. 

The primary process that rubber undergoes when it enters 
a rubber mill after weighing, is washing. As a rule this is 
done with clear water. At the same time, certain acids and 
foreign substances that are contained in the rubber are not easily 
soluble in water, and yet may be easily removed. The first thing 
to do, therefore, is to know what is to be expected in various 
grades of rubber. 

There is no question but that the differences between varying 
grades of rubber, besides being due to a somewhat different chem- 
ical composition, are also due in a measure to varying methods 
of collection and coagulation. It is undoubtedly true that 
no one method of collection would be best for all kinds of 
rubber gathered, even if it were possible. At the same time, it 
is of interest to the practical rubber manufacturer to know pretty 
nearly what systems are pursued, and particularly what ingre- 
dients are added, to produce coagulation, as the presence of cer- 
tain residues may affect his compounds. 

Smoking rubber is the system with which the world at large 
is most familiar, and is practised in the Amazonian forests in the 
collection of Para gum. Several kinds of palm nuts are used to 
produce a thick smudge, but those ordinarily used are from the 
Urucuri palm (Attalea excelsa). This smoke has been found by 
analysis to consist mainly of acetic acid and creosote, the latter 
being a well known preservative of rubber. Fine Para rubber is 
nearly always smoked in this way. Coarse Para is air dried. 
Ceara rubber is also, to a certain extent, smoked in the gathering, 
the palm nut used being that of the Eucturbe edulus. There is 
also a kind of gum tree found in the forests of the Isthmus, and 
where it is impossible to get palm nuts, its wood is used for the 
coagulating smoke. 

Amole Juice. — A native process for coagulating the milk of 



36 GRADES OF CRUDE RUBBER. 

the rubber tree, which prevails throughout Central America, 
involves the use of an alkaline decoction made from the juice of a 
plant called "achete" or "coasso" {Ipomcsa bonor-nox, Linn., and 
also Calonyction speciosum) . This is combined with rubber milk 
in the proportion of i pint to i^ gallons of the latter. During 
coagulation the vessels are often heated from 165° to 175° F. 
After coagulation, the rubber is dried for twelve or fourteen days. 
The kinds of rubber coagulated in this fashion are Mexican, Nic- 
araguan, and in fact almost all of the rubbers that come under the 
head of Centrals, and are obtained from the Castilloa elastica. 

Acetic Acid. — Used in coagulating Hevea latex in the Far 
East. 

Alcohol. — One of the best general coagulants, but too costly 
to be commercially available. 

Alum. — This is used all through the isthmus of Panama, and 
in coagulating Accra rubbers and other African sorts. Pernam- 
buco rubber is also treated with a water solution of Alum, as is 
the Nicaraguan at times. 

BosANGA. — The juice of the Costus afer, a seed, used in the 
coagulation of the latex of Landolphia in the Lopori district in 
Central Africa. 

Beta Separator. — The invention of Mr. John Hinchley 
Hart, F.L.S., of Trinidad. This is an arrangement by which the 
latex placed in the upper compartment is washed, filtered, and 
coagulated. The machine known as the Beta separator works 
somewhat on the principle of the cream separator. 

CouTiNHo's Machine. — ^This is a wooden cylinder about 20 
inches in diameter, set horizontally, revolving by a crank and so 
arranged that smoke is let into the inside through the cylinder 
shaft. The latex, by the revolution of the cylinder, is distributed 
over its inner surface and there smoked and coagulated. 

Coyuntla Juice. — This is an astringent juice made from 
the Mexican weed of that name. When the rubber milk is 
gathered, it is placed in earthenware vessels and whipped with 
the weed, which causes coagulation. The Mexican rubber known 
as Tuxpam is treated in this way. 

Centrifugal System. — Another form of coagulation, that 
has recently been tried with considerable success, is the using of 



COAGULATION. Z7 

a centrifugal machine which removes the watery contents from 
the gum, and produces a marvelously clear elastic rubber. 

Danin^s machine for smoking rubber is a revolvable cylin- 
der, through openings in the end of which smoke is forced, the 
latex first having been introduced through the other end of the 
cylinder. The cylinder being rotated, the latex spreads itself 
over its inner circumference and is carried past the discharge end 
of the smoke conduit and thus coagulated. The machine is the 
invention of Joao Roso Cardoso Danin, of Para, Brazil. 

Formic Acid. — Used instead of acetic acid in coagulating 
Hevea latex. 

FuMERO. — A machine patented by G. van den Kerckhove, of 
Brussels, Belgium. The apparatus is simple, the latex being 
guided by the hand over the smoke and the rubber produced in 
ball form uniformly cured. The apparatus designs to do scien- 
tifically exactly what the Amazon rubber gatherers do crudely 
in smoking Para rubber. 

Heat, Air, Sunlight. — Various rubbers are coagulated 
simply by the exposure to slight artificial heat, to the sunlight, or 
merely to the air. Such are the coarse Para rubbers, certain of 
the Centrals, African, and East Indian rubbers. Fiji rubber is 
coagulated in the mouths of the natives, and some Angola rubber 
on the arms and breasts of the natives. 

Helper Process. — This consists of the addition of a solution 
of acetic acid, and is based on the knowledge derived from the 
analysis of the smoke of the Urucuri nuts. 

KoALATEX. — ^A proprietary preparation used in Ceylon and 
the Federated Malay States for coagulating the latex of the Hevea 
Brasiliensis. 

Lime. — A final process in the coagulation of rubber in India 
is the washing over with lime. Collins also mentions the use of 
lime in connection with the coagulation of Para rubber. 

Lime Juice. — Lagos rubber and some other African sorts 
are coagulated by the addition of a little lime juice, which is added 
as the milk flows from the vine. 

NiPA Salt. — A salt obtained by the burning of the plant 
known as the Nipa fruticans. Is used in the coagulation of 
Borneo rubber. 



38 GRADES OF CRUDE RUBBER. 

Machacon Juice. — Cartagena rubber, which is gathered 
carelessly, is coagulated in a hole in the ground by the addition of 
the juice of the root of the "machacon" — a strongly alkaline 
solution. 

PozELiNA. — A preparation intended to keep rubber latex in 
a fluid condition until the time of curing. The ingredients used 
in making the preparation are secret. The headquarters for its 
sale are at Para, Brazil. 

PuRUB. — Another name for hydrofluoric acid, when prepared 
as a coagulant of rubber latex. 

Salt. — Many kinds of low grade rubber are coagulated by 
the addition of salt or brine. Borneo, for instance, is coagulated 
in that way. Madagascar rubber receives a treatment of salt- 
water. Mangabeira rubber is treated with a mixture consisting 
of I part of salt to 2 parts of alum. Nicaragua rubber is also 
often coagulated with salt. 

Seringuina. — A chemical product for retarding for any 
length of time the coagulation of rubber latex. Is said to con- 
tain no corrosive elements. When the latex is finally smoked the 
substance evaporates entirely. It is the invention of Dr. Cerqueira 
Pinto, of Para, Brazil. 

Soap and Wood Ashes. — The medium grade rubbers all 
through Central America are often coagulated by the use of soap, 
and where that is not plenty, of a strong lye from wood-ashes. 

Spirits of Wine. — This is used sometimes in the coagula- 
tion of Balata. 

Sulphur Fumes. — According to James Collins, rubber of 
the Para varieties is sometimes exposed to the action of the fumes 
of melted sulphur, which affects coagulation. This process, how- 
ever, is very rarely followed. 

Torres System. — In addition to the natural methods de- 
scribed above, there are several that give some evidence of an 
intelligent study of the milk and the substances best adapted 
for this work. Under the Torres system a liquid is made by a 
secret formula, from the roots and fruits of certain South 
American palms, which, when added to the milk, preserves it 
from curdling, so that it will keep for weeks. It can thus be 
transported to a convenient place for smoking. 



OXYDASES IN RUBBER. 39 

OXYDASES IN RUBBER. 

Why rubber is dark in color may with propriety be treated 
here. The discovery by Dr. David Spence, whose investigations of 
the latex of various rubber trees have been most profound as well 
as practical, of an active enzyme which has an oxidizing effect, is 
of much interest to rubber manufacturers. The result of this 
line of experiment and research will undoubtedly one day be a 
pure crude rubber with all the nerve and strength of the present 
dark colored product. Dr. Spence's description of enzymes is here 
appended : 

"These enzymes are probably, as I learned, present in the 
protein of the latex of all rubber producing plants, and so act 
upon the insoluble portion of the protein that it is converted into 
colored products, which impart the dark color to the rubber. In 
my original work I determined that the temperature at which the 
oxidizing enzymes are destroyed lies very close to the point where 
in general other similar enzymes perish. To obtain rubber only 
slightly darkened, it seems, at first glance, only necessary to 
destroy the active enzymes in the latex or the rubber by heating 
above the sterilizing temperature, 75° C. But this method of 
destroying the enzymes by means of heat is not so easily accom- 
plished in practice, and this fact leads me to the belief that in 
the latex and in the rubber there was a heat-resisting agent, 
zymogen, which slowly changed into active enzymes. 

"1 found, for example, that freshly cut pieces of Para rubber, 
washed thoroughly with water for more than an hour to remove 
the strongly colored soluble matters, gradually darkened and 
after exposure to the air finally became entirely black. Potassium 
cyanide, a mercury chloride solution or acetic acid, failed to pre- 
vent the dark coloration, or at least after the above solutions were 
completely removed by washing. I made many experiments with 
the latex of Funtumia elastica, but found without exception that 
heating the latex or the rubber prepared therefrom even to 
100° C. for half an hour was insufficient to alter the tendency to 
turn dark, 

"It is known that certain natives on the West African coast 
obtain rubber from the latex of Funtumia elastica by heating it 
with water until the separating rubber particles coalesce into 



40 GRADES OF CRUDE RUBBER. 

balls. Nevertheless, I have seen no sort of rubber prepared in 
this manner in which the effect of the active oxydase enzyme 
was not plainly observable. 

"Since the oxidizing enzyme is very stable towards heat, 
the best method for handling the latex to secure only faintly 
colored rubber appears to be the one presented previously by me 
and now repeated here. By this method the enzyme itself is to be 
removed as completely as possible before coagulation. The latex 
is diluted with water before the coagulation and the agglomerat- 
ing rubber particles washed well (this applies at least to Funtumia 
elastic a) in order to remove the oxidizing enzyme as well as other 
foreign matter from the rubber. In this manner a snow-white 
rubber is obtained. Yet to prevent as much as possible the bane- 
ful effects when using the boiling process a substance having a 
noxious action against the enzyne but a harmless one towards 
rubber could be utilized. 

"Many experiments to discover a body which would render 
innocuous the oxidizing enzyme have been fruitless. So, from a 
practical standpoint, the destruction of the oxidizing enzyme is 
not as simple a matter. There are a number of difficulties to 
overcome, and, only when the nature and properties of the 
enzyme are more closely investigated, may we hope to ascertain 
a practical method for the removal of this substance." 

Synthetic Rubber. — Every year there is more or less news- 
paper prominence given to Synthetic Rubber discovery and dis- 
coverers, but so far absolutely nothing has been accomplished 
commercially. The producers of alleged Synthetic Rubber work 
along a variety of lines. There is, jfirst and most dangerous, the 
line of fraud where real rubber disguised is put forth as a cheap 
synthetic production. This procedure has been the means of ex- 
tracting many dollars from the pockets of the credulous. There 
is another class of honest but somewhat ignorant inventors who 
make products that in some respects are similar to rubber, and 
which they believe are equal to or even better than rubber. They 
use oils, gums, cellulose, in fact, almost anything that will 
produce a waterproof plastic. These products are often of value 
in connection with rubber and sometimes when used alone, but 
never yet have anywhere near equaled the crude material. 



CHAPTER II. 

SOME LITTLE KNOWN RUBBERS AND BASTARD OR PSEUDO GUMS. 

From time to time reports come in from all over the 
tropical world regarding the discovery of gums, some of which 
are similar to India-rubber, while others are more like Gutta- 
percha. In a few instances these gums have appeared on the 
market, in due time, under various names and have been useful. 
This is not the rule, however, and it is due to a variety of 
reasons. The first, perhaps, is the scientific attitude of those who 
primarily examine the samples received at the great centers of 
civilization. Unless gums are of high grade, and bear promise of 
being nearly as valuable as a good grade of India-rubber or Gut- 
ta-percha, they are usually pronounced as worthless, or nearly so. 
These same experts, it is well to remember, condemned reclaimed 
rubber and substitutes, which may lead the manufacturer to sus- 
pect that his wants are not always appreciated by the learned. It 
is possible, of course, that the scientists and experts are right, and 
that it would have been better had reclaimed rubber or substitutes 
never been known. Nevertheless, rubber manufacturers are ever 
in the market for them, and would welcome many of the pseudo 
gums and find large uses for them, if once they were within reach. 

Aside from the scientific attitude is the indifferent attitude of 
the gatherers in their native wilds, of the importers who see 
little profit in such cheap gums, and of the manufacturers them-, 
selves, who wait until a neighbor has tried something new before 
venturing to experiment. 

It is only sufficient to recall what is needed in rubber com- 
pounding to see how many of these gums could be made valuable. 
For example, sometimes simple stickiness is called for, in another 
case only insulating qualities and stickiness, in still another, water- 
proofing qualities and stickiness, and, it is well to add here, 
where only one valuable quality exists in a gum others can 
often be supplied. As a matter of fact, in the present state of 
compounding and manipulation, the presence of resins is not 
heeded, short life can be overcome, and intractability can be done 
away with. 

41 



42 LITTLE KNOWN RUBBERS. 

A few years ago an American rubber manufacturer at- 
tempted to secure from Mexico a quantity of the bark from a 
small tree which was believed to yield rubber, with a view to 
extracting the gum, by the boiling process. His agent, not under- 
standing the instructions given, had enough of the shrubs cut off 
at the ground to make a steamer load, and shipped them entire — 
wood and all. A liberal yield was obtained of a gum equal in 
quality to a good grade of Centrals. The undertaking did not 
prove profitable enough, however, to cause it to be repeated. But 
in time others became interested in the product of the plant in 
question, with the result of developing the present large produc- 
tion of Guayule rubber, which is treated more fully in another 
chapter. 

It is with the hope that some of the gums mentioned in the 
following pages may be brought before the rubber manufacturers 
the world over, that space has been given to them. 

Abba Rubber. — This is an African rubber, from Lagos. It 
probably is the product of the Ficus Vogelii. It is low grade 
rubber and cures soft and short. There is a large percentage of 
resin in the milk. The tree is widely distributed, and the product 
is thought to enter largely into Lagos rubber. The trees are 
most abundant in Grand Bassam, and grow rapidly to great size, 
single trees often yielding lo or 12 pounds in a season. The milk 
is coagulated by adding vegetable acids and boiling. The rubber 
is bright red. It contains about 55 per cent, rubber and 45 per 
cent, resin, and forms 30 per cent, of the latex. The washing 
loss is 10 to 14 per cent. One report is that the latex of this tree 
is mixed with that of Funtumia elastica, the mixture being called 
by the natives "aba-odo." 

Abyssinian Gutta. — An adhesive acid gum of an earthy 
brown color, similar to common gutta in external appearance. 
Softens in water, but keeps a very great elasticity. On drying 
it remains exceedingly adhesive, therefore could not be used in 
place of Gutta-percha, but with proper treatment would undoubt- 
edly make an excellent friction gum. 

Almeidina. — This comes from West Africa, particularly 
from the Cameroons and Angola, and has been found in the Solo- 
mon Islands. Its source is a shrub with succulent stems, all of 



ALMEIDINA—BAKA GUM. 43 

which are tapped. The milk is boiled and the resultant balls 
dried in the sun. It conies to market in small and sulphur- 
colored nodules, resembling potatoes, for which reason it some- 
times has been called "potato gum." When broken open, these 
balls look like putty, and although quite brittle when cold, the 
gum easily softens in warm water and may be drawn out in 
threads, which are possessed of some elasticity. It is completely 
melted at 240° F., and remains rather sticky after melting. It 
almost completely dissolves in cold benzine; in fact, nearly all 
of the solvents ordinarily used in rubber manufacture dissolve it. 
It mixes and dissolves with rubber in almost any proportion and 
up to 25 per cent, at least. Not only does it not injure the rubber, 
but is said to be beneficial to it. In working on the mill a pungent 
vapor arises from the mass, which, however, has no poisonous 
effect. In using this gum, a little caustic soda sometimes is added 
to the water when it is being washed; some manufacturers add 
tannic acid. Animal or vegetable fixed oils do not dissolve Al- 
meidina, and therefore when mixed with it are apt to rot it. 
Mixed with Gutta-percha this gum is practically indestructible. 
The name "Almeidina" is that of the first important shipper of 
the gum; in England the spelling "Almadina" has come into use. 
The gum is known also as "Euphorbia gum." Warburg and 
Jumelle say that Almeidina comes from Euphorbia rhipsaloides, 
which must not be confused with E. tirucalli. Berry gives 
Almeidina 82.78 per cent, resin, and 9.40 per cent, hydrocarbon. 

Amazonian Resin Rubbers. — The valley of the Amazon 
contains various trees and plants that are caoutchouc producers, 
but which are generally neglected, as the gatherers are seeking 
the more valuable Hevea or Castilloa. At the same time the latex 
of some of these plants has been referred as being used to a con- 
siderable extent for adulterating Para rubber. Among these are 
mentioned the trees known under the native names of Amapa, 
Sucuba, Surva, Tamanguiro, Molango, etc. All of these show a 
marked percentage of resin in the milk. 

Antipolo Gum is being made from Aartocarpus incisa (the 
breadfruit tree) in the Philippines. Antipolo is a town in the 
province of Luzon. 

Baka Gum. — Found in the Fiji archipelago. Comes from 



44 LITTLE KNOWN RUBBERS. 

Ficus obligua (Foret). Used by natives for birdlime. Milk very 
abundant. Gum little known. Samples sent to England were 
reported upon as being suitable for mixing. 

Banana Rubber. — Green bananas yield considerable latex, 
which is 95.7 per cent, water and only 3.9 per cent, rubber. It is 
easily coagulated by boiling. Made from Musa sapientum and 
M. paradisiaca. 

Barta-Balli. — One of the best kown native trees in the 
Guianas. The milk of this tree has usually been mixed with 
Balata milk and is said to give it its reddish tint. The gum when 
dried by evaporation is rather sticky and soft, but when precipi- 
tated in alcohol is dry and firm. Reports from England are 
rather condemnatory as the gum is said to absorb a great deal of 
water in washing, which it retains very obstinately. The same 
rubber, dried by precipitation by spirits of wine, is said to be 
very brittle. Known also as Cumaka-balli. 

Beira Rubber. — Another name for stick rubber, gathered on 
the east coast of Africa, and shipped from Beira. 

Canoe Gums. — From the bark of the breadfruit tree, which 
is found so plentifully in the islands of the Indian archipelago, 
comes a thick mucilageous fluid which hardens by exposure to 
the air. When boiled with cocoanut oil it makes a tough rubber- 
like substance wholly waterproof, and very lasting. It is used 
ordinarily for waterproofing seams of canoes, pails, etc. It is also 
used, when fresh, as a birdlime. Is probably from the Artocarpus 
integrifolia. 

Cape Cattimandu. — Derived from an Euphorbia found at 
the Cape of Good Hope. The juice is so acrid as to give intense 
irritation to any part of the body with which it may come in con- 
tact. The gum has been used as an anti-fouling dressing for 
ships' bottoms, but is little known otherwise. 

Cattimandu Gum. — This is one of the Euphorbia gums, the 
natives using the milk as a cement to fasten knives in their 
handles. Under the influence of heat it becomes soft and viscid 
and when dry is very brittle. It is probably about as useful as 
Indian gutta. Found in Vizagapatam, India, Cattimandu gum 
seems to be from Euphorbia trigona. 

Cativo Gum. — This comes from the sap of the mangrove, 



CHICLE— COORONGITE. 45 

called "Cativo" in the United States of Colombia. The gum is 
fluid at 130° F., and if the temperature be raised to 212° F. it 
is easily filtered and impurities removed, and a somewhat objec- 
tionable smell greatly lessened. The gum is then of a clear red- 
dish brown color. It mixes easily with rubber and is said to pro- 
duce a very tough compound. When vulcanized with 5 per cent, 
sulphur, this gum makes a fine, elastic product. When vulcanized 
with more than 5 per cent, sulphur, it becomes like Gutta-percha, 
and can be sheeted or molded, when warmed. 

Chicle. — A gummy resinous substance found in the Achras 
sapota, a. tree growing abundantly in the warm damp regions of 
Mexico and also in portions of Central America. Chicle should 
be of a whitish color, odorous, and free from impurities, but often 
is adulterated with an inferior pink or reddish soil. It is solid 
and brittle at ordinary temperatures, but becomes plastic when 
placed in hot water. It is quite soft at 49° C. (120° F.). It is 
used chiefly in the United States in the manufacture of chewing 
gums, and to a small extent in England for adhesive plasters. 
It has been used for modeling purposes and for mixture with 
India-rubber for insulation work. The fruit is about as large as 
an apple, though looking more like a quince and is eaten under 
the name of "sapodilla" or "sapotilla" plum. The fruit is pricked 
or sliced and the latex is allowed to ooze out without squeezing, 
so as not to get the other juices. Lateral tapping is used on the 
tree, and 15 to 25 pounds of milk or 5 or 6 pounds of gum may be 
obtained in one season without injuring the tree. The milk is 
coagulated by boiling. Prolonged boiling makes it reddish, 
though some trees are said to yield a red gum. The best Chicle 
is made from highland grown trees. The trees sometimes grow 70 
feet high, and the wood, which is very heavy, takes a high polish 
and is quite valuable. The analysis of Chicle shows 44.80 per 
cent, resin, 17.20 per cent, rubber, 9 per cent, water, and 8.20 
per cent, starch and other matters, on an average. It sometimes 
contains as much as 55 per cent, of resins, when dry. 

CooRONGiTE — Sometimes known as Australian Caoutchouc. 
An India-rubber like material, discovered first near Salt creek, 
a short distance from the coast of South Australia. It was ob- 
served in little hollows of sand and resembled patches of dried 



46 LITTLE KNOWN RUBBERS. 

leather, but it generally occurred in the swamps. It is supposed 
to be of the petroleum series. Some scientific authorities in 
England and America ascribe to it a vegetable origin and regard 
the gum as exuding from a plant or lichen. It is not soluble in 
the ordinary solvents used in rubber work, but after mixing with 
India-rubber is can be put in solution. According to Forster, it 
vulcanizes somewhat as India-rubber does. 

Cow Tree Rubber. — The Cow Tree is very plentiful in tropi- 
cal South America and yields a milk commonly used for food. 
This milk contains considerable Caoutchouc, which is about 30 
per cent, resin. Botanically it is known as the Brosimum galac- 
todendron. Besides Brosimum galactodendron, Warburg men- 
tions another Cow Tree, Couma utilis, an Apocynaceae, growing 
in northern Brazil, while B. galactodendron is an Artocarpeae of 
Venezuela. Couma utilis latex contains rubber, and is used by 
the natives in waterproofing. Cow Tree milk is exceedingly 
hard to coagulate, and evaporation product is completely soluble 
in hot acetone, seeming to indicate absence of any rubber. The 
constituents are mainly fatty matter, possessing neither tenacity 
nor elasticity, according to the German chemists. 

CuMAi Rubber. — From the milk of a tree found on the Rio 
Negro and Uaupes, in Brazil. None comes to market. This 
milk is used by the natives for waterproofing purposes. 

Durango Rubber. — See Guayule. 

Euphorbia Rubber. — See Almeidina. 

Fluvia. — See Pontianak. 

GoA Gum. — Discovered by Senor Da Costa. It is a gum 
that comes from the Mival-cantem, which grows wild in the Cou- 
can district in Brazil, and is also planted for hedges. Chocolate 
in color, softens under heat, is easily molded, and thoroughly 
waterproof. 

GuTTA Bassia. — Found between Upper Senegal and the 
Nile. Has the appearance and apparently many of the properties 
of Gutta-percha. Softens in warm water and becomes glutinous 
at the boiling point. Is soluble in sulphide of carbon, chloroform, 
benzole, and alcohol. Can be kneaded in water as easily as 
ordinary gutta. It may be the same as Karite gutta, which is 



GUTTA-GREK—GUTTA-SHEA. 47 

from Bassia Parkii, though there are other African Bassias which 
are said to yield good gutta. 

Gutta-Grek. — A gum that comes from Palembang, in 
Straits Settlements. It appears very much like India-rubber, but 
is permanently softened and destroyed by heat sufficient to melt 
it. It smells like Gutta-percha rather than India-rubber. 

Gutta Horfoot. — This is a vegetable juice sent in sealed 
tins from the Straits Settlements, which yields a material like 
India-rubber of fair quality. No way of coagulating the juice, 
where it is gathered, seems to be known. 

Gutta-Shea. — Said to be the nearest approach to Gutta- 
percha among African products; obtained from the Shea, Ga- 
1am, or Bambouk rubber-tree (Butyrospermum Parkii). The 
butter is the solid fat contained in the seeds and is used in making 
hard soaps. Gutta-shea is separated from the fat in the course 
of the soap making and is found to be present to the extent of 
from 5 to 75 per cent. A kind of Gutta-percha is also obtained 
from the trunk of the tree in small quantities. Also known as 
"Karite gum." Analysis of the butter shows: Guttalike 25.20 
per cent.; resin 57.13 per cent.; water 5.04 per cent. ; im- 
purities 12.63 P^'' cent. The yellowish butter smells and 
tastes much like cocoa butter. Cazalbo claimed to have 
differentiated two varieties, one yielding a red and the 
other a yellowish gum. The red kind is the more valuable, 
and this tree also yields gum from its trunk, while the 
yellow gum tree does not. It is uncertain whether the yellow 
butter yields any gutta, though the trunk gutta from the other 
variety is comparable to Red Borneo in toughness and in its 
structure. Called also "Karite Gutta" and "Shea butter." 
Knowledge on this subject is still confused and the authorities 
conflict. The two varieties are called "Shea" and "Mana," the 
Shea being the one which yields gutta, and also the more abun- 
dant variety. The branches seem to yield even more than the 
trunk. The milk is allowed to stand in the open air for about 24 
hours, when it partially curdles. The crystalline particles are 
then kneaded into a mass in hot water. However, reports on 
this gum are conflicting, and it is probable that two sources are 
confused. Some advices seem to point to the plum-like fruit as 



48 LITTLE KNOWN RUBBERS. 

the source of both gutta and butter. Fendler and Heim consider 
Karite gutta worthless as a substitute for Gutta-percha. 

Gutta Susu. — Also called "Gutta grip," at Singapore, and 
formerly known as "Assam White," The washing loss is 30 
to 45 per cent,, and the clean rubber contains 14.5 per cent, resin. 
In Java and Sumatra it is generally stored under water. The 
vine is tapped and the gum left to dry on the bark. The milk is 
sometimes gathered and coagulated with salt and boiling, but this 
method is not so good as bark drying. It is a white and remains 
so under water, but darkens on exposure to the air. 

Jelutong. — See Pontianak, 

Jeve^ Jebe_, or Heve (hence Hevea) was the ancient name 
for rubber among the natives of Ecuador, The name was applied 
to a rubber coming principally from the neighborhood of Iquitos, 
Peru, (See Peruvian rubber.) 

JiNTAWAN. — A bastard Gutta-percha mentioned by Thomas 
Hancock in four patents and also by Taylor and Duncan. Prob- 
ably a mis-spelling of "Djintaan soesoa," the same as Gutta-susu. 

LoRANTHUs Rubber. — A sticky non-elastic Venezuelan 
product. Contains 18 per cent, of resin. 

Maboa Gum. — Said to be produced from a species of Ficus 
in Santiago de Cuba. 

Macwarrieballi Gum. — A rubber gathered in British 
Guiana from the Forsteronia gracilis. From the report of the 
director of the Kew gardens, to whom a sample was submitted, it 
would seem that, while the gum is at present unfit for use in 
place of ordinary Caoutchouc, because of its stickiness, it might 
be of value in cements, frictions, and the like. Forsteronia 
gracilis is a vine or bush rope belonging to the ApocynacecB. The 
milk appears to be often mixed with that of Balata or Barta- 
balli, though Macwarrieballi is more like rubber than Balata. 
The vine is very rich in latex. 

Mangegatu Gum. — This comes from Vizagapatam, India, 
and is a gum of the bastard gutta type, similar to gutta trap, and 
is said to come from the Ficus Indica. 

Mandarnva Rubber, — A low grade of South American 
gum, somewhat like Ceara rubber. Little known. Is said to 
grow on the dry arid uplands of the interior. Is one of a number 



MANGA-ICE—PALA GUM. 49 

of gums that bear the natives names, "Cauchin," "Pau," and 
"Massaranduba." 

Manga-ice Rubber. — Argentine republic. It is very abun- 
dant. Produces good rubber. 

MuDAR Gum. — ^This comes from an Asclepiad, commonly 
known as gigantic swallow wort (Calotropis giganteas). The 
shrub is found throughout the southern provinces of India and 
grows to a height of from six to ten feet. Produces a gutta-like 
substance, which becomes plastic in hot water, and in other ways 
acts somewhat like Gutta-percha. It insulates badly, but is rec- 
ommended for waterproofing. Analysis: Rubber, 16.92 per 
cent.; rosin, 83.08 per cent., according to Warden (1885). 
Hooper found 25.54 per cent, of a rather poor rubber, and 62 per 
cent, resin. 

Mule Gum, — Another name for Ceara rubber. 

MusA Rubber. — A gum expressed from the peel and leaves 
of the banana and pisang plants. No gum yet on the market. 
Process patented in England by Otto Zurcher, of Kingston, 
Jamaica. Also called "Banana Rubber" (which see). 

Neen Rubber. — A rubber-like gum said to be produced by 
an insect, reported from Yucatan. The insect belongs to the 
coccus family, feeds on the mango tree, and swarms in those 
regions. It is of considerable size, yellowish brown in color, and 
emits a peculiar oily odor. The body of the insect contains a 
large proportion of grease, which is highly prized by the natives 
for its medicinal properties in skin diseases. When exposed to 
great heat, the lighter oils of the grease volatilize, leaving a 
tough wax which resembles shellac. When burnt this wax pro- 
duces a thick semi-fluid mass, like a solution of India-rubber. 
An "ant wax" or lac is found in Madagascar, and is secreted by 
two insects, Garcardia Madagascariensis and Gascardia Perrieri. 
The former secretes a white gum, containing 52 per cent, of resin. 
The latter secretes red gum, with 46 to 48 per cent, resin. The 
two gums have the same value. 

Pala Gum. — Found in Assam and Ceylon. The wood and 
the bark are valued in India for their medicinal qualities. The 
tree yields an abundant milky juice, which after coagulation 
acts something like Gutta-percha. It readily softens in hot water 



50 LITTLE KNOWN RUBBERS. 

and takes impressions, which are retained when cold. Also 
known as "Indian Gutta-percha." Comes from the Dichopsis 
elliptica. It has been used as an adulterant of Singapore gutta 
for some years. It was used also as birdlime or cement and keeps 
well under water. Is hard and brittle when cold. The resin or 
crystalban is easily removed by boiling alcohol, and the residue 
appears to be a very fair gutta. 

Palo Amarillo. — A varnish-like gum from the latex of the 
Mexican tree Euphorbia fulva. Analysis of the latex gives 34 
per cent, gum and 6 per cent, resin. So far the gum is not sus- 
ceptible of vulcanization and is not elastic. 

P. F. U. — A good rubber, not now obtained commercially, 
the source of which was the Colorado desert weed, the Picra- 
denia florihunda utilis. 

PicKEUM Gum. — See Guayule. 

PoNTiANAK is a cheap inelastic gum imported from Borneo 
for use as a friction and filler. It takes its name from the town 
of Pontianak, and is known also as "Jelutong," this being the 
import name in the United States, and sometimes as "Fluvia" 
and "Cambria." It is white and looks like marshmallow candy, 
and smells strongly of petroleum. Oxidizes readily on exposure 
to the air. Pontianak gum, according to eminent authority, 
comes from the tree Dyera costulata. It often comes mixed with 
the milk of local Willoughbeias. The Dyera costulata sometimes 
grows 150 feet high and yields 100 pounds of gum when cut down. 
Pontianak is about the same as Almeidina in quality. Berry finds 
in Jelutong 75 to 76.55 per cent, resin, and 16 to 19 per cent, 
hydrocarbons. Pontianak wood is much used in making Chinese 
shoes. 

Root Rubber. — A rubber obtained from the roots of semi- 
herbaceous plants known as the Carpodinus lanceolatus, Landol- 
phia Thollonii, and others. Very abundant in the open grassy 
country of Angola and the Congo Free State. (See Thimbles.) 

Sarua Rubber. — Found in the Fiji archipelago, from Alsto- 
nia plumosa. Formerly collected largely, now but little comes to 
market. Natives take no interest in its collection. Is soft at first, 
but hardens after a time and becomes inelastic. Is about the color 
and consistency of putty. Natives collect juice in three months 



SUSU-POKO—TUNO. 51 

and it coagulates almost at once. Comes from stems and leaves. 
No juice in trunk of tree. 

SiEBA Gum. — See Tuno. 

Susu-POKO (meaning English tree milk). — A gum from a 
tree growing in the Malay peninsula, used in the place of Gutta- 
percha, after being cleansed and treated with chloride of sulphur. 
Mentioned by Leonard Wray in 1858. 

Talotalo Gum. — Found in the Fiji archipelago. Comes 
from Tahernaemontana Thurstoni. The gum is hard, gutta like, 
and without elasticity. Also called "Kau Drega." The milk is 
thin, but the tree grows large, up to two feet in diameter, and it 
is the best rubber source in the Fiji islands. 

Talaing Rubber. — An almost black rubber which, when 
cut into, is white and porous presenting a honeycombed appear- 
ance, the cavities being filled with a watery fluid. It is quite 
tough and elastic and appears to be of good quality. It comes 
from a creeper which is abundant in the Philippines, in Malacca, 
and Indo-China. The juice is very abundant, and is coagulated 
by being boiled in water. 

Tirucalli Gum. — This is a Euphorbium gum, from the 
Indian plant known as milk hedge. The milk of this plant is used 
for various purposes, chiefly medicinal, in India, and has been 
suggested as a substitute for Gutta-percha. Like Gum Euphor- 
bium, it has a very acrid character, and the collection of it is a 
very dangerous operation to the eyes. When dry it becomes 
very brittle, but when warmed in water is quite elastic. 

ToucHPONG Gum. — This is without doubt a rubber gum, 
entirely distinct from Balata. The rubber dries in strips on the 
trees, and what little of it comes to market has not been recog- 
nized as a distinct sort. Samples sent to England, however, have 
been favorably reported on. It is found throughout the Guianas. 
Probably from Sapium biglandulosum. Spelled "Touchpong" by 
Jenman; "Touchpong" by Morris; "Pouckpong" by Dr. Hugo 
Miller. 

Tung is a trade name applied to a gum gathered principally 
in Nicaragua and Honduras. It is the product of what has been 
called the "sterile rubber tree" and also the "male rubber tree" 
of Nicaragua. The milk is coagulated with the aid of heat. The 



52 LITTLE KNOWN RUBBERS. 

gum is but slightly elastic, is very sticky when heated, and is 
cheap. It is used as a friction gum, and is also mixed with 
Balata in the manufacture of belting. Sometimes it is sold under 
the name "Seiba gum," its identity being lost by the ingenious 
massing and manipulation under water. Nicaragua rubber 
adulterated with "Tuno" in coagulation soon hardens and loses 
its elasticity. Also spelled "Toonu" and "Tunu." It is derived 
from Castilloa, tunu, and called locally "caucho macho" or male 
rubber. Though it has a bad reputation, Mr. E. Poisson has drawn 
excellent rubber from this same tree in Costa Rica. Tuno gum 
usually runs over 80 per cent, resin. Berry gives it 80 to 86.13 
per cent, resin, and 3.50 to 7.06 per cent, hydrocarbons (gutta- 
like). 

Yellow Gutta. — This comes from the Sunda Isles, from 
the genus Payena. It is practically a compound of India-rubber 
with two resins. One of these is crystallizable and the other is 
pitchy. If the raw material be treated with boiling alcohol the 
resins are taken off and the remaining product appears to be 
good India-rubber. Berry describes Yellow Gutta as "a gum of 
dual composition containing the hard resins characteristic of 
chicle, and the elastic caoutchouc-like hydrocarbon characteristic 
of rubber." It is more like rubber than gutta. The analysis gave 
80 per cent, resin and 12.58 per cent, hydrocarbons (rubber?). 
The resin looks like chicle resin, and has a saponification value 
of 104. 1, with a trace of acid. However, there are several guttas 
which are yellow. 



CHAPTER III. 

I. DIVISIONS IN RUBBER MANUFACTURE AND PRIMARY PROCESSES IN 
MANIPULATING THE GUM. 

The foremost European manufacturers of rubber goods, as 
a rule, make everything in the Hne of compounded rubber, hard 
or soft, and in addition often are producers ' of Gutta-percha 
goods. In the United States, on the other hand, the tendency has 
been to speciaHze the industry, and as a result it has divided itself 
naturally into the following general lines: Mechanical rubber 
goods; Tires, pneumatic and solid; Molded work; Sundries, 
druggists', surgical, and stationers'; Dental and stamp rubbers; 
Surface clothing; Carriage cloth; Mackintoshes and proofing; 
Boots and shoes; Insulated wire; Hard rubber; Cements; 
Notions; Plasters; and Reclaimed rubber. 

The following brief description of the manipulation of rub- 
ber in these various lines is given simply because there are super- 
intendents and managers who are experts in one line, say, for 
example, of Druggists' sundries, but who may be wholly 
unfamiliar with even the machinery used in other lines. 

Mechanical Rubber Goods. — This line of rubber manufac- 
ture, which is also known in Europe as technical rubber goods, 
embraces all the heavier combinations of India-rubber, metal, and 
fabric which are used in engineering and industrial lines. It 
covers, for example, belting, packings, hose, and special articles 
of almost endless variety and description. 

This portion of the rubber business has always been the 
pioneer in the production of new compounds, new processes, and 
better and heavier machinery. Its manufacturers always have 
welcomed new grades of rubber, have been the first to utilize those 
that were a drug on the market, because of lack of knowledge as 
to their manipulation, were familiar with the uses of reclaimed 
rubber while yet other lines were simply considering its use, and 
with hundreds of compounds and cures, with a broad knowledge 
of industrial achievement in all lines, they have often pointed 
the way for manufacturers in other lines to follow, to the better- 
ment of their goods or their pockets. 

53 



54 DIVISIONS OF THE MANUFACTURE. 

The mechanical rubber goods factory has, to begin with, the 
same general outfit in the way of machines for manipulating 
the crude gum as have the other lines. Their mixing mills, how- 
ever, are often heavier, and their calenders run at higher speeds, 
while they have, in addition, enormously heavy hydraulic belt 
presses, huge vulcanizers, and scores of special machines designed 
for individual problems required for their line of work, or per- 
haps for a single factory alone. The kind of vulcanization used 
in this work is (i) open steam heat, where the goods are buried 
in French talc or wrapped in fabric; or (2) dry heat, where they 
are confined by molds, and held in a steam press during the cure ; 
or (3) where the goods, as in the case of belts, are molded 
between the platens of the press itself, while curing. Even in this 
line of work there are some concerns that only do special parts 
of it. For example, there are certain large factories that make 
only certain types of packings, which have a world-wide sale, 
and on which they are run continuously. Many of these mills 
also are large producers of tires. 

Boots and Shoes. — ^The manufacture of rubber boots and 
shoes, although apparently a simple business, not only requires 
large capital, but is one that has often been overtaken by disaster. 
It is a matter of common knowledge that, given the same com- 
pounds, the same machinery, and the same skilled workmen, no 
two mills are able always to turn out exactly the same grades 
of goods. Quality is one ingredient that may or may not be 
added to the goods, no matter how honest the endeavor. That 
there are reasons for this, no one can doubt, and that the day 
will come when this branch of manufacture will be an exact 
science is probably true. That, however, will entail a definite 
knowledge of rubber from the moment it first sees the light as 
creamy liquid exuding from the tree, through every event in its 
life — in coagulation, transit, storage, factory manipulation, com- 
pounding, calendering, curing, its death in the service of man, 
and its later resurrection in the process of reclaiming. Nor is 
this all. There will be a need for exact information regarding 
the ingredients added in the course of compounding, their rela- 
tion one to another, mechanically and chemically, so long as 
they be joined together. This, coupled with atmospheric and 



DRUGGISTS' SUNDRIES. 55 

climatic conditions, not to say a profound knowledge of the errors 
and accidents due to the ignorance, prejudice, or carelessness of 
the ordinary workman, constitutes so complex a problem that suc- 
cessful manufacturers to-day feel fairly safe in frankly stating 
to would-be competitors that they have no need to hide their 
formulas, as they are but a small part of the problem. 

In the complete rubber shoe plant there are found, for initial 
equipment, washing rolls, mixers, refining mills, and calenders 
such as most of the other lines employ. In addition, there are 
special calenders, with engraved rolls for shoe-upper work ; others, 
also, with engraved rolls for soleing; presses for molding boot 
heels, sole-cutting machines, and, of course, vulcanizers. As this 
class of goods is cured by what is known as the "dry heat" — that 
is, by being confined in dry, hot air for several hours — it will 
readily be seen that it is a radically different business from 
mechanical rubber goods, for instance. These dry heaters are 
simply large air-tight rooms, fitted with steam pipes for heating, 
lined with tin, double walled to prevent radiation, into which 
hundreds of pairs of boots or shoes are run on skeleton cars, to 
undergo the process of vulcanization. The manufacture of rub- 
ber footwear in brief, therefore, consists in washing, drying, com- 
pounding and calendering the rubber, the cutting of the cal- 
endered sheets into various shapes for cementing over lasts in 
the shapes desired, the varnishing, and the dry heat cure. 

Druggists', Surgical and Stationers' Sundries. — This 
part of the rubber business entails more skillful manipulation and 
more finesse in manufacture than almost any other line. An atom- 
izer bulb, for example, must be graceful in shape, with delicately 
smooth surface, of good color, and either of the non-blooming 
variety or so near it that the sulphurous efflorescence will be so 
slight as to pass unnoticed, while in mechanical goods a length of 
garden hose may be of any color, may bloom until crusted with 
sulphur crystals, but if it "stands up to work," it is the best, 
and is beautiful in the eyes of the trade. 

The question of colored rubber is one that has interested this 
branch of the business from its inception. In none other is so 
much white rubber made and, incidentally, none others get such 
good effects. This insistence by customers for white goods and 



56 DIVISIONS OF THE MANUFACTURE. 

by physicians for black containing no trace of lead has entailed a 
deal of trouble upon this trade, for the manufacturers until re- 
cently could not go into the open market and buy a high grade 
of white recovered rubber, while of black there is ever an ample 
supply, and in black goods to suit the physician he is forced to 
substitute a dry bulky vegetable black for oxide of lead or white 
lead, and then not get so good a result. 

The machinery used is very similar to the equipment of a 
mechanical goods factory, but the scale is smaller. Washers, 
grinders, calenders, tubing machines, steam vulcanizers, and small 
steam presses are the machines used. Naturally special machines 
are employed in certain parts of the work, but their use is limited 
to a few factories and to comparatively insignificant specialities. 

The feature in this trade which stands out most distinctly 
from other rubber lines is perhaps the manufacture of hollow 
work, as atomizers, syringes, breast-pumps, and a host of other 
balls and bulbs. The parts for these are cut from sheets of com- 
pounded rubber, cemented together at the edges, inflated to the 
general shape of the mold and cured in an open steam heat. In 
order that the ball may perfectly fill the mold during the cure, a 
few drops of water or a little ammonia are put inside of it which, 
swelling under the heat, develops pressure enough to perfectly 
shape it and add to its outer surface the finish found on the inner 
surface of the mold. 

The difficulties that manufacturers in this line experience in 
making perfect goods are legion, as they are in other lines. They 
are added to by the fact that the trade, as already indicated, 
demands articles of beauty from a gum that was designed for 
utility solely. A trace of black in a white compound may spoil 
hundreds of dollars' worth of goods, nor can such trace be rubbed 
off, scoured out, or eradicated, after vulcanization. Hence, the 
whites, blacks, reds, and other colors must be mixed on separate 
mills, and the trimmings and scraps kept sedulously apart. 

Pure gum — that is, rubber compounded only with sulphur or 
some other vulcanizing agent — is also largely produced in this 
line. For example, it makes what is known as dental dam, the 
pure sheet used by dentists. This is generally a sulphur com- 
pound cured in open steam. Certain manufacturers, however, 



CLOTHING— TIRES. 57 

practice the vapor cure with good success in making these goods. 
This cure gives a beautiful finish, but if it be not done with great 
skill it may be disastrous to both the workman and the goods. 

Dental dam, surgical bandages, and stationers' bands 
represent the highest priced and least compounded goods, 
while stopples, erasive rubber, and common tubing represent 
the other extreme. Between the two is a latitude that allows 
of a variety of combinations and compounds that no man can 
number. 

Clothing, Carriage Cloth, Mackintoshes, and Proofing. 
— This business may be handled, in a measure, as the 
mechanical goods business is ; that is, the gums mixed by 
heat on ordinary mixers, and then spread by calenders on the 
fabrics which give the articles their strength. This is the 
manner in which rubber surface clothing is run. The machin- 
ery is simple, since, in clothing, the parts are cemented 
together and cured in dry heat. In carriage cloths, after 
calendering, the goods are grained on embossing rolls, var- 
nished, and run into a dry heat. 

The mackintosh and proofing business, however, is some- 
what a departure from this. Here the gum, after mixing dry, 
is usually put in churns with a cheap solvent, and reduced to 
a solution. It is then applied to the cloth with a knife 
spreader. 

For double-texture work, a simple doubling machine 
brings two surfaces together. A portion of the business that 
has divided itself from the rest, is what is known as proofing 
for the trade. Here manufacturers simply coat the cloth and 
sell it to others, who make it up into garments, or anything in 
fabric or rubber for M'^hich there may be a call. The mackin- 
tosh manufacturer to-day not only is familiar with a great 
variety of rubber gums and ingredients used in compounding, 
but is also an expert in fabrics, as his business is really closely 
akin to the tailoring business. 

. Tires. — Although the tire business seemed at first to be a 
natural part of the mechanical rubber goods business, it really 
proved itself, later, to be a business wholly distinct from it. Even 
the large manufacturers of mechanical goods who began tire 



58 DIVISIONS OF THE MANUFACTURE. 

making on a considerable scale, keep this part of their business 
distinct from other branches as a rule, running it as an entirely 
separate department. A large business is done in pneumatic tires 
for bicycles and motor cycles, but it is much surpassed by the 
production of pneumatic automobile tires. The knowledge gained 
through the manufacture of pneumatic bicycle tires (which, by the 
way, was one of the hardest problems that the rubber trade ever 
solved) has proved wonderfully effective in developing the skill 
necessary to make this heavier and more important article. This 
tire, like the bicycle tire, is built up of frictioned duck, with an 
outer coating of high-grade rubber carefully vulcanized. While a 
variety of compounds undoubtedly is used in its manufacture, it is 
hardly possible that any manufacturer will be able to sell a very 
low grade of goods. In other words, the life of the tire is so 
important, and the purchaser so anxious for a good article, that 
adulteration or cheapening to any great extent is not a danger. 
An adjunct of this business is the manufacture of inner tubes 
which has assumed very large proportions. 

The general machinery used in making tires is the same that 
is used in the work of preparing rubber in the other lines. 
There are two general classes of tires manufactured, however: 
those that are molded, and those that are made in such a way 
that they can be wrapped for the process of vulcanization. 
Wrapped goods, of course, are cured in an open heat. In the one 
case the tires are cured in presses, sometimes in nests of molds, 
and sometimes in vulcanizers. Various ingenious and valuable 
processes and special machines have been invented, and are now in 
use in this line. An industry that has grown up in connec- 
tion with the tire business, and that has increased the practical 
knowledge of the uses of the rubber wonderfully, is that of tire 
repairing, which is carried on in many places and to an important 
extent outside of the rubber factories proper. 

A part of the tire business that is of great interest is the 
making of the solid or cushion molded tire used on light 
vehicles. A very large business is done in this, the work being 
a simple process of mixing the prepared compound, forcing it 
into shape through a tubing machine, and molding. Of even 
greater importance has been the business of producing heavy 



INSULATED WIRE— HARD RUBBER. 59 

solid tires for trucks, motor buses, fire engines, and freight 
wagons. Many rubber manufacturers have specialized in this 
line and their yearly product is very great. 

Insulated Wire. — The manufacture of insulated wire, 
either with India-rubber or Gutta-percha insulation, is a line 
that is more distinctly apart from other portions of the rubber 
business than almost any other. For Gutta-percha, the gen- 
eral machinery used is described in the chapter on that gum. 
Where India-rubber is used, the crude gum is treated in the 
same way as in mechanical goods. It may be forced over the 
wires by tubing machines, or welded together in strips that 
are run between grooved rolls. 

Braiding machines are also a part of the outfit for weav- 
ing the protective covering, and the wire is usually wound on 
huge drums and vulcanized in open steam heat. Polishing 
machines, testing machines, and various mechanical contri- 
vances are, also, a part of this equipment. The line of com- 
pounds used is one adapted almost wholly to this industry, 
and embraces a great variety of ingredients and gums that are 
treated specifically under their special heads, elsewhere in this 
book. 

Mold Work. — A part of the rubber business that belongs 
either to the mechanical or to the druggists' sundries line has, 
during the past few years, detached itself from the rest, so 
that to-day many large factories are run simply in producing 
small mold work. They have the usual equipment of rubber 
machinery, special appliances for filling and emptying molds, 
and the usual aggregation of hard and soft metal molds that 
run into thousands of dollars in a short time. The extent to 
which this business is carried may be imagined when it is 
known that one company runs 300 presses on this work, and 
many have from 20 to 50 in constant service. When it is 
remembered that very rarely are two compounds exactly 
alike, it will be seen that, in this line also, the expert com- 
pounder has a wide field for thought and experiment. 

Hard Rubber. — In spite of the hundreds of substitutes for 
vulcanite, or hard rubber, that have been produced, the demand 
has in no way fallen off, and mills are running full to-day on the 



6o DIVISIONS OF THE MANUFACTURE. 

production of this semi-metal. The old fashioned compound, con- 
sisting of 2 pounds of India-rubber to i pound of sulphur, is 
still in use in certain goods. Modem progress and chemical 
knowledge have, however, added a great many compounds for 
specific uses, so that almost any degree of quality, or hardness, 
or price is now furnished on call. 

The business, primarily, is a simple one, the hard rubber 
machinery being like that used in other lines. In the manipula- 
tion of the gum for vulcanization, and in its finish, however, 
special machines are necessary. The finishing machines are 
lathes, saws, buffers, etc., somewhat similar to what might be 
used for turning hard wood. The mechanical factories often do 
a little in hard rubber in the line of valves, and the druggists' 
sundries mills often make their own syringe fittings, but the bulk 
of the business in America is done by mills that make only 
vulcanite the year around. 

Cements. — Many rubber factories are run wholly on this 
line of work, the gums being mixed as in a general rubber busi- 
ness, put into solution in churns, and sold by the barrel for an 
infinite variety of purposes. Hundreds of different formulas are 
in use for cements sold for general and specific purposes. The 
leather shoe business, for instance, calls for a dozen or more special 
cements. The bicycle business has need for a great many grades 
of what are known as tire cements. Stickiness, waterproof 
qualities, durability, and cheapness in their goods are sought 
by all cement manufacturers, and, in order to secure these quali- 
ties, skill is demanded in compounding in no way inferior to 
that shown in other lines of rubber work. 

Dental and Stamp Rubber. — The manufacture of unvul- 
canized gums for the use of dentists and rubber stamp manufac- 
turers is an industry apart from other lines, and one that has 
assumed large proportions. The rubber is compounded and 
sold by the manufacturer, and cured and finished by the dentist 
or rubber stamp manufacturer. In stamp work the rubber is 
compounded for soft rubber and many hundreds of tons are sold 
during the year while, of course, the dental rubber is so mixed 
that under the cure it becomes vulcanite of the color desired. 



WASHING AND CALENDERING. 6i 

The machinery for this work consists chiefly of washers, mixers, 
and calenders. 

Notions. — A department of the rubber business, the impor- 
tance of which is not generally appreciated, is that which takes 
in such work as waterproof dress bindings, dress shields, chil- 
drens' aprons, diapers, etc. Several large factories manufacture 
these goods, mixing their rubber by the usual processes, coating 
it on calenders, and having special machines for forming and 
curing the goods in their special shapes. In the manufacture 
of dress shields, the vapor cure is often practiced very suc- 
cessfully. The rubber manufactures of this class are not by any 
means inexpert compounders. They have also, perhaps, gone as 
far as any in deodorizing rubber goods, so that the smell of the 
gum or any compounding ingredients is wholly done away with. 

Plasters. — There are few factories that keep wholly to this 
line of work. It is perhaps as simple as any part of the rubber 
business, a fair grade of rubber being washed, dried, and mixed 
by the usual methods, and calendered upon the fabric that forms 
the base of the plaster. These goods are not vulcanized, of 
course. Though a variety of gums and medicaments is used in 
this compounding, the range is probably smaller than any other 
line of rubber manufacture. 

II. THE WASHING, MIXING, AND CALENDERING OF RUBBER. 

The very first manufacturing process in the manipulation of 
rubber of any kind, and for any use, is that of the cleansing. This 
is usually done by passing the gum again and again between cor- 
rugated rolls, w^hile fine streams of water remove the various im- 
purities that are exposed by the tearing action of the rolls. These 
impurities are bits of vegetable substances, earth, sand, etc. The 
old type of washer for removing these was a couple of corrugated 
rolls 6 or 8 inches in diameter, and 12 or 14 inches in length. 
Modem methods, however, have introduced larger rolls, until 
to-day one machine, when it is the highest type of three-roll 
washer, will cleanse enough gum to keep a huge factory busy. 

Some rubbers are so full of sand that it is almost impossible 
to remove it wholly. For this purpose is used a tub with a false 
bottom made of fine wire, and also "with a stirrer. "Thimbles," 



62 DIVISIONS OF THE MANUFACTURE. 

for instance, after being run through the washer, are put in the 
tub without any attempt at sheeting, and stirred until a large 
portion of the sand is removed. 

Another type of washer is one- that is quite similar to a paper 
engine ; in fact, paper engines are often used in rubber washing. 
The special value of this type is that the rubber in its movement 
about the tub is floated more or less, and the sand and earthy 
matters sink to the bottom, while the bark and vegetable matters 
can be seen and easily removed. 

Some manufacturers, following Austin G. Day's ideas, have 
used alkaline solutions in washing certain gums, to neutralize the 
vegetable acids, and it is a question if it might not be as well to 
use dilute acids to neutralize the strongly alkaline qualities of 
gums that go through certain kinds of coagulation. Some fac- 
tories also examine the coarser grades of gums chemically, and 
give them a treatment to remove odor. As a rule, however, 
manufacturers rush them through the washing machines, sheet 
and dry them, and get them into the mixing mills as soon as 
possible. 

The drying of rubber, according to earlier practice, required 
a great deal of time. It was the boast of more than one rubber 
mill that no Para rubber was used by them until it had been dried 
for a year. The manufacturers of mechanical rubber goods were 
the first to break away from this tradition. In many cases they 
found, when there were rush orders on hand, that they must put 
on their mills gum that was practically just off the washer, and 
mix it, or else lose orders. Of course, they were forced to get 
most of the moisture out, or neutralize what was left, and they 
learned incidentally that they got a stronger compound with the 
green gum than with the "seasoned," whence the belief grew up 
that the months and years of drying were not necessary, as had 
before been supposed. In addition to this, some of them learned 
that long drying meant oxidation on the outside, or the turning 
of rubber into resin, which further increased their doubt of the 
wisdom of the slow drying process. 

These thoughts once entertained, it was not long before 
various plans were introduced into the drying, for hastening the 
removal of the moisture. The simplest of these, of course, was 



WASHING AND CALENDERING. 63 

artificial heat, and the presence of a fan for removing the 
moisture laden atmosphere. Later developments have brought 
about a process for drying rubber very cheaply at quite a high 
heat, lasting only a few hours, that gives it to the man who runs 
the mixer, hot from the dryer, and that does away with the 
expensive process of breaking down. This latter idea is to some, 
of course, as revolutionary as was the first thought of quick 
drying, but that it is wholly in the line of progress, is proved by 
the fact that it has now been used for a number of years in many 
whose goods stand very high. 

The milling of crude rubber is simply putting the dry rubber 
which is found in a tough, intractable sheet, on hot rolls, and run- 
ning it until it gets to be a softened homogeneous mass. The 
gum, when this is accomplished, is ready for mixing. These mix- 
ing rolls are run at different speeds and are called friction rolls, 
and the various adulterants and ingredients that are to be incor- 
porated with the rubber are pressed into a softened gum by their 
revolution. 

No general rule can be laid down for mixing in all lines. An 
expert compounder knows that certain gums should be mixed on 
cool rolls, and others under considerable heat. His knowledge 
of specific compounds teaches him to hasten mixing in many cases 
where another, without skill, would require very much more time 
to get the same result. In some cases the ingredients are put 
in together, in others it is necessary one is put in last. Some 
have dissolved substances that would make the rubber stick to the 
rolls like glue unless they be put in at just the right time; 
others have so large a proportion of earthy matters that, unless 
the gum be humored, it apparently will not take them in, and so 
on. Each line of work and, in fact, each factory has its own 
special methods, and often one or more skilled mixers who can 
handle compounds that none of the others seem to be able to do 
anything with. 

The use of the calender is simply to sheet the goods so that 
they may be easily made into the desired forms. The simplest 
form of calender is a mixing mill with the key that normally 
holds one roll in place withdrawn, so that both run by even 



64 DIVISIONS OF THE MANUFACTURE. 

motion, which is used in many small factories where nothing but 
molded work is made. 

The modern sheeting calender is ordinarily a three-roll 
machine. It is sometimes made with four rolls, however, and 
these rolls may be almost any size, the widest for rubber work 
being more than 80 inches. No little skill is required for 
running the calender on a variety of stocks, nor can any general 
rules be laid down for calender work. This is proved by the 
value that is set upon good calender men, and by the difference 
that there is between the work of a good one and a poor one. 
There are as many different kinds of calenders as there are pat- 
terns of mixing mills. A sheet calender has smooth rolls, and is 
for running absolutely smooth goods. In shoe work there are 
engraved rolls, pebbled rolls, and soleing calenders engraved in 
the likeness of the shoe sole. The carriage drill business has em- 
bossing calenders, and so on. A type of calender that is useful in 
most lines of work is known as the friction calender, the rolls in 
which, run at uneven speeds, drive the gum deeply into the fabric. 

Where India-rubber is handled in solution there is used in 
place of the calender a spreading machine, known under various 
names of "Yankee flyer," "English spreader," "Doughing 
machine," etc. In this a sheet of rubber is spread on the cloth 
by being placed on an endless apron of the fabric, the apron 
running over the roll against which hangs a heavy knife. A very 
thin coating of the rubber solution is constantly scraped off this 
surface, which then passes over hot drums or steam chests, evap- 
orating the solvent. 



CHAPTER IV. 

VULCANIZING INGREDIENTS AND PROCESSES. 

The average rubber manufacturer is not interested in exactly 
what vulcanization is — that is, what it is chemically. It is 
sufficient for him that India-rubber mixed with sulphur and 
heated results in a new compound, vulcanized rubber. It is, 
to be sure, interesting for him to know how much sulphur is 
combined and how much uncombined, and the effect that high 
temperatures, time, and pressures have upon resultant com- 
pounds. Nearly all of these problems, however, are individual 
to his own work, and are solved by him along practical lines. 
Considering compounded India-rubber as a dough which is 
fashioned into shape and baked, is about as far as the manipu- 
lator of rubber goes. 

The means for vulcanizing India-rubber in general use 
are roughly two: the heat cure and the cold cure. Consider- 
ing the first, a great variety of goods is cured in open steam 
heat and is kept in shape during vulcanization, either in 
molds or by being wound with strips of cloth or buried in 
pans of French talc. This is the wet heat and such goods are 
cured in vulcanizers, big and little, of which there are scores 
of types. A different application of heat is what is known as 
dry heat, where goods are put in a hot room without wrapping 
or mold protection, and left until vulcanization is effected. 
Another heat cure which at one time was very largely used, 
but to-day has practically disappeared, was what was known 
as solarization. This consisted in exposing fabrics coated with 
a thin skim of rubber to the rays of the sun, which effected a 
surface cure. 

What is known as the cold cure has been practiced since 
the days of Goodyear, and within the last ten years has been 
much resorted to in the manufacture of certain lines of goods. 
This, in turn, divides itself into two methods — the acid and the 
vapor cure. In the former one-half pound of chloride of sul- 
phur is mixed with four pounds of bisulphide of carbon. The 

65 



66 VULCANIZING INGREDIENTS. 

goods are dipped in this solution and afterwards treated with 
an alkaline wash. The vapor cure is where the fumes of 
chloride of sulphur are set free in a heated room or cabinet in 
which the rubber goods are hung so that all of the surface is 
affected. When the cure is far enough advanced the further 
action of the chloride of sulphur fumes is stopped by ammonia 
fumes. 

While Charles Goodyear's patents for the vulcanization 
of India-rubber by the use of sulphur and heat were in force, 
a marvelous amount of ingenuity was shown in the attempts 
to accomplish the same results by the substitution of other 
ingredients for sulphur, either with or without the use of 
heat. These experiments and inventions embrace vulcaniza- 
tion, by means of chlorides, nitrates, nitrites, fluorides, bro- 
mides, iodides, and phosphorets of about all the common 
earths and metals, and also many gases such as sulphurous 
acid gas. The majority of these experiments have been lost 
sight of, partly because the Goodyear process is now open to 
the w^orld, and partly because, for the majority of goods, the 
sulphur and heat cure is not only the cheapest, but the easiest 
to accomplish. It may be well, however, to review and 
record the experiments in this line, as there is no doubt that 
for special lines in rubber manufacture many of them have a 
suggestive value to-day. 

One of the very first ingredients to which inventors and 
experimenters turned their attention was zinc. The veteran 
rubber manufacturer Jonathan Trotter described a process 
for preparing a vulcanizing material which he called hyposul- 
phite of zinc. It was made from a solution of caustic potash 
saturated with flowers of sulphur and then treated with 
sulphurous acid gas. This solution he mixed with a saturated 
solution of nitrate of zinc, forming the precipitate that he 
desired. He used 3 pounds of hyposulphite to 10 pounds of 
rubber, curing from 3 to 5 hours, at 260° to 280° F. 

Another American, E. E. Marcy, some years later pat- 
ented a compound of hyposulphite of zinc and rubber which 
is apparently almost identical with Trotter's discovery, 
although he disclaimed similarity, and also made public the 



EARLY INVENTORS. 67 

process, in which he used a combination of hyposulphite of 
zinc and sulphide of zinc, the compound being 2 pounds of 
rubber, i pound sulphide of zinc, i pound hyposulphite of 
zinc, and other ingredients as deemed necessary. These 
goods were of a beautiful white color, were said not to bloom, 
and did not need the sunning process then in use. At the 
same time they depended upon sulphur and heat for whatever 
vulcanizing was accomplished. 

Another attempt to get a good substitute for sulphur was 
in the production of what is known as sulphite or hyposul- 
phite of lead. James Thomas describes at length a compound 
in which he mixes hyposulphite of lead and artificial sulphide 
of lead in equal proportions, his compound being for vulcan- 
ization, 2 parts by weight of India-rubber and i part of the 
vulcanizing material. 

Following this thought came E. E. Marcy again, who 
mixed sulphide of lead and carbonate of lead in the propor- 
tions of 2 parts of sulphide of lead, i part carbonate of lead, 
and 2 parts protoxide of lead in place of the carbonate. 

Then Oscar Falke and Albert C. Richards brought out a 
compound consisting of 6 parts India-rubber, 2 parts sulphide 
of antimony, and ^ part sulphite of soda, curing at 270° to 
280° F. 

A. K. Eaton, in no uncertain terms, disclaimed vulcaniza- 
tion by the use of free sulphur, but claimed to be the first to 
use sulphide of manganese. He also gave a formula for 
making it, which was by mixing intimately 44 parts of 
peroxide of manganese with 32 parts of sulphur, and exposing 
the mixture to heat in a covered crucible. He vulcanized 
several hours, from 250° to 310° F. 

George Dieffenbach claimed sulphite of alumina as an 
ingredient which, in connection with heat, would bring about 
vulcanization. He used this in a compound for a dental 
rubber, which had for its basis India-rubber, amber, linseed 
oil, sulphide of cadmium, oxide of tin, vermilion, and pulverized 
feldspar. 

Charles T. Harris cured India-rubber by combining it 
with an artificial sulphide of bismuth, which he explained as 



68 VULCANIZING INGREDIENTS. 

being the artificial tersulphide, or polysulphide of bismuth. 
He describes this as being a heavy black powder, and the 
compound which he advised for soft rubber was lOO parts 
India-rubber, 75 parts carbonate of lead, and I2|^ parts poly- 
sulphide of bismuth, cured in a dry heat at 245° F. for i^ 
hours. 

Henry W. Joselyn discovered that shale combined by 
heat with sulphur formed a sulphide which could be used in 
curing rubber, and hastened to patent it. 

Andreas Willman brought out a process for combining 
India-rubber with "anhydrous chlorides, sulphates of alkalies" 
and powdered coke or coal, and claimed that his best result 
came from chloride of ammonium and coke. His compound 
was made up of litharge, lampblack, and powdered coke, in 
connection with from 2 to 10 per cent, of his vulcanizing 
mixture. 

Edwin L. Simpson formed a vulcanizing compound by 
mixing benzoin gum with pulverized sulphur, and boiling it 
in linseed oil. It was used in a dry heat, the compound being 
I pound of India-rubber, 2 ounces vulcanizing compound, 8 
ounces litharge, and 8 ounces whiting. 

J. A. Newbrough manufactured a vulcanizing material 
which he called acid resin, made of turpentine and sulphuric 
acid. This he incorporated in India-rubber in the proportion 
of 6 ounces of acid resin to i pounl of India-rubber, and 
cured at 300° to 320° F. 

The use of selenium as a curing agent was discovered by 
E. E. Marcy, while connected with Horace H. Day, then 
prominent as a rubber manufacturer. He advised the use of 
equal parts of India-rubber and powdered selenium, and, to 
produce a glossy finish, he added selenium carbonate and 
whiting. 

At the same time there were many other inventors who 
were experimenting with processes that were somewhat in 
the line of the well-known Parkes cold-curing process. For 
example, it is a matter of history that the late Joseph Banigan, 
early in his career as a rubber manufacturer, cured wringer 
rolls by an acid process. 



PARMELEE— MEYER. 69 

Dubois C. Parmelee invented a process which he called 
"hermizing," to distinguish it from curing or vulcanizing, 
instead of the Parkes process, in which the solution of chloride 
of sulphur and bisulphide of carbon was used. He recom- 
mended briefly a solution as follows : 10 pounds of coal-tar 
naphtha, in which was dissolved i pound of sulphur. Into this 
solution he passed dry chlorine gas until it assumed a fine 
yellowish-green color. This solution he used as a dip for such 
goods as would be cured by the acid treatment. Parmelee 
also claimed the discovery of a solution made of coal-tar 
naphtha, bisulphide of carbon, and a solution of sulphur in 
bromine, mixed with this. 

H. A. Ayling patented a cold curing process in which 
carbon spirits, one of the petroleum series, was mixed with 
chloride of sulphur, instead of the usual bisulphide of carbon. 

Referring again to the suggestions of chlorine in the 
working of rubber, R. F. H. Havermann reduced India-rubber 
to a solution and subjected it to the action of chlorine. He 
also, in a later patent, described the washing of the chlorine 
out of the rubber by alcohol, and the addition of ammonia and 
lime, the result being, according to his specifications, a white 
hard rubber. 

Working in the same line, John Helm, Jr., dissolved 
India-rubber in benzine and mixed it with liquid chlorine in 
the proportion of 12 ounces of chlorine to i pound of gum. 
His claim was that he could get rubber of any color and of 
any degree of hardness by this process. 

In the line of hard rubber manipulation and vulcaniza- 
tion, L. Otto P. Meyer (then connected with the India-Rubber 
Comb Co.) patented a process for curing vulcanite in a vessel 
wholly or partly filled with water, the water in which the 
rubber was contained being in a tight receptacle, and the heat 
being raised above 300° F., the pressure of the surrounding 
steam, keeping it from vulcanizing. This obviated the danger 
of burning, and was of great value in the production of certain 
goods. 

While these and other inventors were trying to cure 
rubber without sulphur, and without interference with the 



70 VULCANIZING INGREDIENTS. 

Goodyear patents, certain others were at work on other gums. 
For example, John Rider, who was at the head of a Gutta- 
percha company, produced what he called mettallothyanized 
Gutta-percha. In this, he first heated the Gutta-percha, then 
mixed 3 pounds of hyposulphite of lead and zinc with 8 
pounds of gum, and sometimes added also a little Paris white, 
or magnesia. He then put the compound from 2 to 10 hours in 
a dry heat and cured it at 280° to 320° F. 

John Murphy changed this compound somewhat, by ad- 
vising the incorporation of sulphur in the proportion of 2 to 
6 ounces of sulphur to 10 pounds of Gutta-percha. This sul- 
phur, by the way, obviated the preliminary heating of the 
Gutta-percha, which was supposed to volatilize the ingredients 
that had before rendered it unvulcanizable. 

A curious process for the manufacture of hard rubber was 
also brought out by William Mullee. In this, just as soon as 
the rubber was washed, the sheets were immersed in the 
sulphur bath, heated to 220° F. The water and other impu- 
rities in the rubber were said to be extracted by the action of 
the heated sulphur. After boiling 30 minutes, the sheets were 
removed with tongs and washed to prevent crystallization. 
They were then subjected to the same process a second time. 
The rubber was then compounded in the old fashioned way, 
on rolls, the proportions being 17 to 24 ounces of sulphur to 
16 ounces of rubber. The claim for this was that the com- 
pound when cured was tougher than any others ever known. 

William Elmer prepared what he called "elastic selenide 
of Caoutchouc." He first dissolved the India-rubber in bisul- 
phide of carbon, placed it under pressure, and heated gradu- 
ally. When brought to about 300° F., the liquefied selenium 
was put into the apparatus drop by drop, the solution in the 
meantime being kept in constant motion. This elastic selenide 
he claimed to be semi-fluid which, when evaporated, possessed 
all the characteristics of India-rubber. 

The Parkes cold-curing process is so widely known as to 
require but a word. It is based on the invention of Alexander 
Parkes, and depends upon the faculty that chloride of sulphur 
has for vulcanizing India-rubber. (See Chloride of Sulphur.) 



AMORPHOUS SULPHUR. yi 

A curious process, similar to that of Parkes, is Caulbry's 
process, by which it is claimed rubber can be vulcanized at 
ordinary temperatures, by using an intimate mixture of 
chloride of sulphur and dry chloride of lime. During this 
mixture, and when the smell of the chloride of sulphur 
will be noticed, the temperature of the mixture will rise, the 
mass becoming plastic by the softening of the sulphur. If a 
mixture of this kind, in which sulphur is in great excess, be 
added to the solution of India-rubber in bisulphide of carbon, 
the rubber will be vulcanized at an ordinary temperature, or 
perhaps with a slight warming. Chloride of sulphur used pure 
is too corrosive in its effect on India-rubber; it is therefore 
reduced in all cases. Only thin articles can be vulcanized in 
this way. 

A patent taken out in England by Edmond Gamier 
relates to the vulcanization of India-rubber by the use of alum. 
Previously alum processes for curing had not been very success- 
ful, but this patent had some novel features. It called for par- 
ticularly dry alum treated with a solution of terebinth of benzol 
and shellac, or some similar gum. In use he took 8 ounces of 
alum and a solution composed of i part gum and 20 parts benzol. 
He mixed the ingredients that are usually employed in the manu- 
facture of rubber, specifying 3 pounds of whiting, i pound 
barytes, 8 ounces lime, i^ pounds oxidized oil, and 8 ounces of 
India-rubber. When these had been thoroughly mixed together 
and specially treated, alum was incorporated with them and well 
compounded, being passed through the mixing rollers cold. It 
was then calendered. 

Amorphous Sulphur. — The fusing of i pound of sulphur 
with 4 ounces of Canada balsam produces what is known as 
Amorphous Sulphur, which is said to cure rubber so that it will 
have no tendency to bloom. The preparation has a very pun- 
gent sulphurous odor. Patented by Dr. Wilhoft, of New York* 

Artificial Sulphuret of Lead. — There are several com- 
binations of lead and sulphur which may be produced artificially, 
That one containing the most sulphur has a composition of 13 per 
cent, of sulphur and 86 per cent, of lead. Its specific gravity is 
about 9.4. In color it is black. It melts at a strong red heat. 



72 VULCANIZING INGREDIENTS. 

The other sulphur compounds of lead have much less sulphur, 
one containing but 9 per cent, and the other only 4 per cent. 
What is known as hyposulphite of lead is a mechanical mixture 
of the above first named, with a suitable percentage of sulphur 
to effect vulcanization. It is also known in the rubber trade as 
"Eureka compound" and "Burnt hypo." These compounds when 
pure — that is, when free from adulteration — are of great value. 
They produce goods that are jet black and have little odor and 
are free from bloom. They are reckoned as the safest vulcanizing 
agents, as it is almost impossible to burn goods that depend upon 
their presence for cure. They are used in either dry or wet heats. 

Barium Sulphide is prepared from heavy spar by making a 
dough of it with charcoal and oil and subjecting it to a white 
heat. Sulphides of the alkaline metals, potassium, sodium, cal- 
cium, and barium, will vulcanize rubber, whence the term "alka- 
lized rubber." 

Bromine. — A heavy deep red volatile liquid, possessing a 
most peculiar and unpleasant odor, and giving off vapors most 
irritating to the air passages and lungs. Its very name means 
stench. It has a powerful action upon most organic bodies, color- 
ing animal matter brown, while it bleaches coloring matters, dyes, 
etc. Its specific gravity is 3.18. A piece of sheet rubber dipped 
into bromine is vulcanized instantly. It is somewhat soluble in 
alcohol, and very soluble in ether, bisulphide of carbon, chloro- 
form, etc. Newbrough and Fagan filed two patents in the United 
States for the use of bromine in vulcanization, both with and 
without iodine. By adding to iodine -J its weight of bromine, 
proto-bromide of iodine is formed, which is said to combine with 
India-rubber and produce a hard compound on being exposed i 
hour to a temperature of 250° F. To prevent the forming of an 
explosive the iodine and bromine were separately treated with oil 
of turpentine to which had been added a quarter of its weight of 
sulphuric acid. It was then mixed with the gum in the propor- 
tion of 2 pounds II ounces to every pound of gum. Bromine 
was also used alone by these inventors, the material after molding 
being plunged into the liquid, and left there long enough to 
harden. To prevent the hardening of the material while in the 
bath, chloroform or any other solvent of rubber was added in the 



CHLORIDE OF SULPHUR. jz 

proportion of i part to 9 parts of bromine; in other words, the 
rubber vulcanized in the air after its withdrawal from the liquid. 
Chloride of Sulphur. — Sulphur and chlorine form three 
compounds, the monochloride, the dichloride, and a tetrachloride 
of sulphur. The substance usually used in the arts is the first 
named or a mixture of the first two. It is an oily liquid of the 
specific gravity 1.7, and boiling at 239° F. It has a pungent 
smell and decomposes on contact with water or watery vapor. 
Pure chloride of sulphur is of an orange yellow color of great 
density. It fumes strongly when exposed to air, throws off the 
vapors of hydrochlorine, and is quite poisonous, severely attacking 
the mucous membranes. It is widely known as the active agent 
in Parkes's cold-curing process, where it is used in connection with 
bisulphide of carbon. A common formula for this is chloride of 
sulphur, I part by weight, bisulphide of carbon, 30 to 40 parts by 
weight; immerse from 60 to 80 seconds. In the manufacture of 
balloons and toy balls, the solution is a far weaker one. That for 
the outside dip is 10 parts of chloride of sulphur to 100 parts 
bisulphide of carbon, while for the inside it is 16 parts chloride of 
sulphur to 100 parts bisulphide of carbon. When it was com- 
mon to cure proofed cloth by the cold process, it was done by 
wetting its surface with a mixture of 5 to 10 parts of chloride of 
sulphur, dissolved in 100 parts of bisulphide of carbon, then run- 
ning the fabric over heated drums to evaporate the mixture. In 
the sulphurization of oils for rubber substitutes chloride of sul- 
phur plays a most important part, nearly all of the amber and 
white products being produced by its use. It also has a curious 
effect upon bastard gums, giving some of them temporarily the 
elasticity and appearance of high grade rubber. 
Gold Brimstone. — See Sulphur. 

Golden Sulphuret of Antimony. — This is prepared from 
black antimony by boiling it with caustic soda and" sulphur for 
some time. The liquid is then clarified by filtration or settling 
and the clear part treated with a dilute acid, preferably muriatic 
or sulphuric. A golden yellow precipitate is formed which should 
be well washed in water, and dried at not too high a temperature 
in a darkish place. The results of this operation well carried out 
are constant and the composition should be : Antimony, 60.4 ; sul- 



74 VULCANIZING INGREDIENTS. 

phur, 39.6. Golden sulphuret of antimony heated in a tube will 
give off sulphur which will deposit on the cool sides of the tube 
away from the flame and the residue will turn black, being indeed 
the black sulphide of antimony. All samples of this compound 
should be tested for free acid, by shaking up a little of 
the powder in a test tube with cold or hot water, and testing the 
water afterwards with some barium chloride and blue litmus 
paper. A white cloud in the first place and the reddening of the 
paper in the second place indicate the presence of more or less 
free sulphuric acid. Golden sulphuret prepared with muriatic 
acid will not respond to the first test, but will to the second. 

Golden Sulphuret or Antimony Red (pentasulphide) is 
used more largely than any other form of antimony in rubber 
work. It is frequently adulterated, sometimes with carbonate of 
lime, oxide of iron, or oxide of antimony, all of which tend to 
harden the rubber. Also called Orange Sulphide of Antimony. 
Properly used, this ingredient produces some of the best effects 
found in vulcanized rubber, in color, texture, and durability. It 
should never be mixed on a very hot mill, should be sheeted and 
placed in cooling racks if it is not to go right to the calender, 
and should be cured in as low a heat as possible. The ideal result 
will be of a golden yellow color, with a very slight bloom, if any. 
It is used only in high cost goods. 

Honeycomb Sulphur. — A vulcanizing compound made by 
boiling a pound of sulphur and two ounces of benzoin gum 
together, i pound of this material being mixed with a quart of 
boiled linseed oil. 

Hyposulphite of lead. — See Artificial Sulphuret of Lead. 

Iodine is manufactured from seaweed and is a black-gray 
substance occurring in small shining scales. Its specific gravity 
is 4.94 and it fuses at 239° F., giving off violet vapors. It is 
readily soluble in alcohol, benzol, chloroform, and sulphide oi 
carbon. In addition to the formula given under the head of 
bromine, Newbrough and Fagan patented the combination of 
iodine and sulphur. In this the sulphur was boiled in turpentine, 
and the oil decomposed and deposited with the sulphur at the 
bottom of the vessel was used in the operation, after being 
washed in dilute sulphuric acid and dried. The iodine was 



LIQUID CHLORINE. 75 

treated in the same manner to prevent explosions. Equal pro- 
portions of the two were melted together and incorporated in the 
proportion of 2 ounces 5 drams to i pound of rubber. After 
shaping, the articles were put in a vulcanizer and during the first 
fifteen minutes exposed to a dry heat, gradually increasing to 
320° F., remaining there 5 minutes, then dropping rapidly to 250° 
F., and continuing for an hour. 

Liquid Chlorine. — Qilorine is a greenish yellow gas at all 
ordinary temperatures. It has strong bleaching properties and 
also a very bad smell and action upon the respiratory passages. 
Under a pressure of 127 pounds to the square inch at 60° F., 
chlorine condenses to a yellow liquid, having the specific gravity 
of 1.33. Chlorine cannot, as a rule, destroy mineral colors or 
blacks produced by carbon. Helm claimed that he was able to 
produce white hard rubber by incorporating chlorine with the mass. 

Liver of Sulphur. — This is really penta sulphide of potas- 
sium, and is obtained by mixing carbonate of potassium together 
with sulphur. It is called Liver of Sulphur on account of its 
brown color. As it is quite volatile it should be kept in well 
closed glass vessels. The fluid for vulcanizing purposes is a con- 
centrated solution of the penta sulphide, about 25° Baume being 
right for use. To cure with it the liquid is brought to the boiling 
point in a porcelain vessel, the articles to be vulcanized being 
immersed in it. This is known as Gerard's process and is said to 
be inexpensive and perfectly safe. 

Milk of Sulphur. — Another name for what is ordinarily 
termed precipitated sulphur. It is fine, light, and grayish white 
in color, but is often adulterated with sulphate of lime. It should 
be kept in a dry place, as it has an afiinity for moisture. 

Nantusi is a vulcanizing agent and preservative for rubber, 
manufactured under a secret formula, and in use in England. 
It is offered as preventing the superficial cracking of rubber 
exposed to the atmosphere; preserving the quality of the 
rubber ; doing away with the possibility of acidification in sulphur 
as ordinarily used; and reducing the cost of the mixing. It is 
said to be a special mixture of paraffine and sulphur. 

Penta Sulphide of Antimony. — The chemical name for 
Golden Sulphuret of Antimony (which see). 



y6 VULCANIZING INGREDIENTS. 

Proto-Chloride of Sulphur. — See Chloride of Sulphur, 

Sulphide of Lead. — Occurs native as galena and is one of 
the ores of lead, having a specific gravity of 7.2 to y.y. Com- 
mercially it is found as a black powder, of specific gravity 6.9. 
Its composition is 86.6 per cent, of lead and 36.4 per cent, of sul- 
phur. Sulphide of Lead is a very useful black pigment, and one 
that is used quite largely in rubber works, as it is a good filler 
and assists in vulcanization. It is often made from pure white 
lead by very simple treatment. It materially assists the resiliency 
of Para compounds. 

Sulphur Lotum. — A name for sublimed sulphur that has 
been washed to remove sulphurous acids, and carefully dried. 

Sulphide of Zinc. — Sulphur forms with zinc two sulphides. 
One of these, the monosulphide, corresponds to zinc blende, 
which, as found native, is of various colors, from yellow to black. 
Its specific gravity is from 3.5 to 4.2. The other is a penta sul- 
phide artificially prepared and occurs in the form of a white pow- 
der. Upon ignition in the absence of air this latter substance 
loses four-fifths of its sulphur, but the temperature at which this 
takes place is too high to render it available as a source of sulphur 
of vulcanization in compounding rubber mixtures. With a slight 
addition of sulphur it is used in the production of white goods. 

Sulphur occurs in a number of different forms, and under 
various names as brimstone, flowers or flour of sulphur, roll sul- 
phur, rock sulphur, etc. Its specific gravity is 1.98 to 2.06. It 
melts at 239° F., thickens and becomes orange yellow at 320° F., 
at 428° it is semi-solid and red, and on carrying the heat higher 
it becomes browner and boils at 788° F. Some of the sulphur, 
now used commercially is recovered from alkali waste, but most 
of it comes from Sicily, where it is found native. It is more 
generally used in rubber works than any other ingredient, and 
in all proportions from 3 per cent, up to 100 per cent, of the 
weight of the rubber. The ordinary form in which it is found in 
the rubber factory is in a yellow powder, known as flowers of 
sulphur. It has a slight affinity for moisture, and careful manu- 
facturers keep it covered from air to avoid the formation of sul- 
phurous or sulphuric acids. Mixed with certain oils by heat, it 
forms the black sulphur substitutes that are often used in rubber 



SULPHUR. 77 

compounding. Sulphur in the form of rolled brimstone is pul- 
verized, sifted, and used in the place of flowers of sulphur, in 
France, and is equally good and cheaper. 

Sulphur Balsam. — A solution of sulphur in fixed oils, con- 
sisting of 2 ounces of flowers of sulphur in 8 ounces of linseed oil, 
used in proofing compounds. 

Vesuvian White. — A special vulcanizing material manu- 
factured in England, for use in the manufacture of tennis balls 
and other goods. 

VuLCANiNE. — ^An English vulcanizing preparation, used for 
both steam and dry heat goods. It occurs either as a white or a 
black powder, depending upon the line of goods on which it is to 
be used. 

VuLCOLE. — A paste furnished in two colors, white and black, 
that, added to certain compounds, prevents blooming. It also 
has the quality of rendering flowers of sulphur inert if used in 
excess, so that 50 to 75 per cent, can be used in an ordinary soft 
compound. 

Garnier, in an English patent, mixes rubber cold (?) with 
shellac dissolved in benzole and adds alum, claiming that the 
product is similar to vulcanized rubber. 

Raymond, in another English patent, uses for vulcanizing a 
mixture of benzine, camphor, chloride of sulphur, and oleic acid. 



The table on the following page indicates vulcanizing pres- 
sure in pounds per square inch in gage, and temperatures by the 
Fahrenheit scale: 



78 VULCANIZING INGREDIENTS. 

VULCANIZED PRESSURES AND TEMPERATURES. 

Pressure Temperature Pressure Temperature Pressure Temperature 

in lbs. in in lbs. m in lbs. in 

per sq. Fahren- per sg. Fahren- per sg. Fahren- 

mch in heit inch in heit mch in heit 

gage. degrees. gage. degrees. gage. degrees. 

7 232.3 39 285.4 71 316.7 

8 234.7 40 286.6 72 317.5 

9 237.1 41 287.8 73 318.3 

10 239.4 42 288.9 74 319.1 

11 241.6 43 290.1 75 319.9 

12 243.7 44 291.2 76 320.7 

13 245.8 45 292.3 77 321.4 

14 247.8 46 293.4 78 322.2 

15 249.7 47 294.4 79 323.0 

16 251.6 48 295.5 80 323.8 

17 253.5 49 296.5 81 324.5 

18 255.3 50 297.5 82 325.2 

19 257.0 51 298.6 83 326.0 

20 258.7 52 299.6 84 326.7 

21 260.4 53 300.6 85 327.4 

22 262.0 54 301.5 86 328.1 

23 263.6 55 302.5 87 328.9 

24 265.2 56 303.5 88 329.6 

25 266.7 57 3044 89 330.3 

26 268.2 58 305.3 90 331.0 

27 269.7 59 306.3 91 3317 

28 271. 1 60 307.2 92 332.3 

29 272.6 61 308.1 93 333.0 

30 273.9 62 309.0 94 333-7 

31 275.3 63 309.9 95 334-4 

32 276.7 64 310.8 96 335-1 

.33 278.0 65 311.6 97 335-7 

34 279.3 66 312.5 98 336.4 

35 280.5 67 313.3 99 337-0 

36 281.8 68 314.2 100 337.7 

37 283.0 69 315.0 

38 284.2 70 315-8 



CHAPTER V. 

FILLERS AND OTHER INGREDIENTS USED IN DRY MIXING RUBBER 
COMPOUNDS. 

India-rubber is compounded for two reasons, the first being 
to reduce the cost without destroying the usefulness of the 
gum, the second being to impart to the gum qualities possessed 
by a great variety of mineral, vegetable, and even animal sub- 
stances. Each of the ingredients treated in this chapter has 
some specific use. While their arrangement may seem a little 
incoherent to the chemist, it will be fully appreciated and 
understood by the rubber manufacturer whose habit of mind 
leads him to reach out into any of the kingdoms — animal, 
vegetable, or mineral — for assistants in compounding problems. 

Acetate of Lead. — A white, sweetish-tasting powder soluble 
in water and alcohol. In its crystalline form it contains about 
7 per cent, of water of crystallization, which is easily driven 
off at a temperature of, say, 80° to 100° F. Its specific gravity 
is : crystallized, 2.3 ; water free, 2.5. Its use in semi-hard com- 
position was patented by both Goodyear and Payen. India-rub- 
ber dissolved in oil, to which has been added acetate of lead, is 
used to fill the pores of certain leathers so that the "filling" shall 
not come through. It is also used in certain varnishes in con- 
nection with Gutta-percha. 

Agalmatolite. — A silicate of aluminum resembling soap- 
stone which is soft enough to be carved with a knife. It has 
no advantages over talc, silicate of magnesia, or soapstone in rub- 
ber use. The largest deposits of this material are to be found in 
China. 

Aluminum Flake. — A curious natural product in the form 
of a white powder, free from grit, with a specific gravity of 
2.58. It is a remarkable heat resistant, is inert in compounds, 
and toughens them. Is used instead of zinc oxide, both for 
color and strength. Is largely used, in rubber work in the 
United States and Canada. 

Aluminite. — A white clay containing a large percentage of 
aluminum (about 30 per cent.) and a certain amount of silica. Its 

79 



8o FILLERS IN DRY MIXING. 

specific gravity is low, and its fusing point 2,400° F. Found in 
the United States. 

Alumina. — The oxide of aluminum and a chief constituent 
of clay. Its specific gravity is 4.154. Ordinarily speaking, it is 
a very inert substance, insoluble, and not readily attacked by 
acids. It is best known in the arts under the forms of 
corundum, emery, etc. As obtained chemically it is a fine white 
glistening powder, feeling harsh and dry to the touch. Eaton's 
formula for the use of oxide of aluminum in making a pure white 
rubber was : India-rubber 40 per cent., oxide of aluminum 55 per 
cent, and sulphur 5 per cent. 

Alundum. — A patented abrasive material made from oxide 
of aluminum or bauxite. 

Amphiboline. — A German earth. When wetted and dried, 
it will not absorb water again. Used in waterproofing, the product 
being non-inflammable. Is mixed with gelatine or size, no rubber 
being used : 34 parts amphiboline, 9 parts gelatine, 2 parts chrome 
alum, 2 parts ammonium sulphate, 53 parts water. 

Anhydrite. — The water-free mineral form of sulphate of 
lime or gypsum. It has a specific gravity of 2.9, and is formed 
artificially by heating gypsum so as to drive off all its water. 
It is white in color and crystalline in form. Gypsum that has been 
overheated in the preparation of plaster of paris and that has 
lost its ability to "set" is pure Anhydrite. It is used as a filler 
in rubber compounding instead of whiting or paris white. 

Antimony. — See Golden Sulphuret of Antimony, Black An- 
timony, and Kermes. 

Argillaceous Red Shale. — A shale that has a large amount 
of clay in it is termed Argillaceous, and the substance mentioned 
in the heading may be briefly termed clay tinctured red with 
oxide of iron. The analysis of Argillaceous clay shows : Alumina 
39, silica 46, water 13, iron, magnesia, and lime 2, It was the 
basis of a well-known oil-resisting compound that for years 
baffled imitation. 

Artificial Sulphuret of Lead. — See Burnt Hypo. 

Arsenic. — A white brittle metal, with a specific gravity of 
4.7 or 2,-7, according to its form. Also a popular term for the 
oxide of arsenic sometimes called the white arsenic, which is a 



ASBESTIC— ASBESTOS. 8i 

heavy white powder of the specific gravity 3.7. White arsenic, 
arsenious oxide, is sHghtly soluble in cold water and to the 
extent of 10 per cent, in hot water. There are several coloring 
matters formed from arsenic, all of which are to he condemned for 
general use. The most familiar are paris green ; realgar, which is 
red, and orpiment, which is yellow. The white oxide is rarely 
used in rubber work, and is to be avoided, as are the greens, 
reds, and yellows. The green has been used in mechanical 
rubber goods, but the color was not a valuable one. Hancock 
vulcanized Gutta-percha with orpiment, and Forster used it in 
"mosaic work" for floor coverings. An anti-fouling compo- 
sition for ships' bottoms is formed of Gutta-percha, copper, 
bronze, and arsenic. Another is formed of: India-rubber 2 
pounds, rosin 7 pounds and arsenic 2 ounces. 

AsBESTic. — The part of the rock remaining after the richer 
veins of asbestos have been extracted. This remainder is a 
purely fibrous material, clearly showing its origin. For 
mechanical uses it is ground fine, and for all sorts of fire- 
proofing purposes is valuable and much cheaper than long 
fiber asbestos. It is mined at Danville, Lower Canada. It 
makes an excellent compounding material for asbestos pack- 
ings, etc., in connection with rubber. 

Asbestine. — A pure fibrous silicate of magnesia, called also 
mineral pulp. It is mined near Gouverneur, New York, 
where is the only deposit at present known where magnesia 
shows so distinct a fiber. It is very largely used in the manu- 
facture of paper, and also as an ingredient in rubber. Appar- 
ently the pulverized mineral is a very strong white powder, 
but in actual use it has not much more covering quality than 
whiting. It was at one time used largely in the manufacture 
of rubber shoes, but, aside from being inert and a good filler, 
was probably no better than whiting, while it was more costly. 
It is often used in white goods, in connection with oxide of zinc, 
to make a light weight compound. It is also known as 
agalite and asbestine pulp. Its composition is: Silica 62, 
magnesia 33, water 4, iron oxide and alumina i. 

Asbestos {Amianthus). — A fibrous silicate of calcium and 
magnesia, also called stone flax, salamander's wool (from an 



82 FILLERS IN DRY MIXING. 

old belief that it was originally made from the wool of the 
salamander), cotton stone, mountain flax, mountain wood, and 
mountain cork. Its specific gravity is 3.02 to 3.1. An analysis 
of the two best known varieties shows : 

Canadian. Italian. 

Silica 40.92 40.25 

Magnesia 33.21 40.18 

Water of hydration 12.22 14.02 

Alumina 6.69 2.82 

Protoxide of iron 5.77 -75 

Soda 68 1.37 

Potash, etc 22 .15 

Sulphuric acid traces .31 

The longest fiber is possessed by the Italian, which is 
sometimes 3 feet in length. The Canadian ranges from 3 to 6 
inches in length, but it is finer, more flexible, and more easily 
separated than the Italian. The mineral divides itself natur- 
ally into three classes : the first, coarse, brittle, very plentiful, and 
cheap; the second, possessing well-defined fibers of a brownish- 
yelow color, fragile, and containing many foreign bodies ; the 
third, with pure white silky fibers which can be woven into 
textiles. A notable use to which asbestos has been put in the 
United States is in the production of the packing known as 
Vulcabeston (which see). Its low conductivity of heat renders 
it particularly useful in steam packings, both for cylinder work 
and for joints, while its incombustibility has long caused it to 
be used for fireproof purposes. There are fibers formed of 
serpentine rock which are much used as a substitute for gen- 
uine asbestos, and answers nearly as well, being, however, 
shorter in fiber and somewhat less durable. Almost all large 
rubber manufacturers produce packings in which there is a 
certain amount of asbestos, often assisted by infusorial earth, 
asbestine, etc. 

Atmoid. — A very light white earthy matter, marketed by an 
English corporation. Analysis proves it to be an almost pure 
silica — quite close, in fact, to infusorial earth. 

Atmido. — A snow-white filler of low specific gravity, free 
from organic matter and indifferent to acids. Used in small 
proportions, is said to increase both strength and resiliency in 



BARYTES—BLUE LEAD. 83 

soft rubber goods. Used in large proportions, it makes a very- 
hard compound, said to resist superheated steam. Manufac- 
tured in Germany. 

Barytes. — ^A heavy white mineral that in commerce takes the 
form of a fine v^rhite or gray powder. It is obtained by grind- 
ing the mineral heavy spar, or by chemical means from baric 
chloride. Its specific gravity is 4.5. It occurs in commerce 
under the names "permanent white" and "blanc fixe." The 
artificially-prepared substance is to be preferred to the finely- 
ground mineral, on account of its less cystalline form. The 
commercial article should always be examined to determine 
its freedom from acid impurities. Barytes is chiefly used as an 
adulterant for white lead and paints. Thus, Venice white con- 
tains equal parts of sulphate of barytes and white lead ; Hamburg 
white, 2 parts to 2 parts of white lead; and Dutch white, 3 parts 
to I part of white lead. It is wholly inert when used as an ingre- 
dient in rubber compounding, and increases the resiliency of 
rubber, and is a make-weight. 

Black Antimony. — A black powder obtained by grinding 
stibnite or antimony ore. It is a sulphide of the metal and is 
met with more or less pure, as it is often prepared from a high- 
grade ore. The sulphur contained in it is unavailable for 
vulcanizing purposes, and if used in compounding it is neces- 
sary to add a sufficiency of sulphur to vulcanize. In the purest 
form, black antimony contains about 28 per cent, of sulphur 
and 72 per cent, of antimony. It is insoluble in water, but 
is dissolved by muriatic acid or by caustic alkalies. From 
its solution in alkali a fine brown-red powder may be obtained 
by treatment with a dilute acid, and this powder, known as 
kermes, has the same chemical composition as that mentioned 
above. Its specific gravity is 4.6. It was formerly used some- 
times as a filler, as it was believed to give a soft effect in 
molded goods. It has been almost wholly displaced, however, 
by cheaper and better ingredients. 

Black Hypo. — See Hyposulphite of Lead. 

Black Lead. — See Plumbago. 

Blue Lead. — Where zinc ores are found in combination with 
galena, or natural sulphide of lead, the two are often smelted 



84 FILLERS IN DRY MIXING. 

together with raw coal and slaked lime, producing a fume 
called blue powder, which is sold under the name of Blue Lead. 
It is an excellent filler, but is not as good as sublimed lead; 
for example, as it does not impart enough resiliency to rubber. 
Its chief merit is its cheapness. A very fine quality of Blue 
Lead, containing considerable lead oxide, is now on the market, 
but this must not be confused with either of the two low-grade 
articles mentioned in these paragraphs. This Blue Lead is of 
exceeding fineness, and gives a peculiarly soft finish to the 
rubber. Used in the place of litharge, it materially assists in 
the cure, and produces a fine black. As it has a high specific 
gravity, it often displaces barytes. Blue Lead is also a name 
given to an artificial aluminous substance occurring either as 
a loose powder or in a concrete form, colored blue by means 
of some kind of blue dye — aniline or logwood — which does not 
contain lead. 

Bone Ash. — See Phosphate of Lime. 

BoNEBLACK. — See Animal Charcoal, 

Bucaramanguina. — A transparent amber-colored, incom- • 
bustible material, found near Bucaramanga, Colombia. It is 
somewhat similar to asbestos, for which it has been mentioned 
as a substitute in the manufacture of packings. 

Burnt Umber. — An earth containing a large amount of iron 
oxide of a dark-brown rust color. As mined, it is called raw 
umber, and the product obtained by calcining it is known as 
Burnt Umber. It is a fairly useful filler in compounding, as its 
action, or rather lack of action, upon rubber makes it safe to 
use. It is used in brown packings and, to a certain extent, in 
maroon goods. 

Calamine. — An ore of the metal zinc, and a carbonate of 
zinc. Ordinary Calamine, which is a silicate of the metal, has a 
specific gravity of 3.6 to 4.4, and is little used in the arts. 
Noble Calamine, or native carbonate of zinc, is a gray or gray- 
ish yellow to brown powder, according to its priority. Its 
specific gravity is 3.4 to 4.4. Its nature is earthy, and heat has 
no action upon it. A little of it is said to toughen soft com- 
pounds. 

Calcium White. — Another name for Whiting. 



CALOMEL— CHALK. 85 

Calomel. — A white, tasteless, and inodorous powder of 
specific gravity about 7.2. It is permanent in the air, but 
should be kept in the dark, as light blackens it. When pure, it 
may be wholly volatilized by heat, but if this cannot be done, 
then the sample tested contains other bodies. Calomel strikes 
a black color under the action of alkalies. It is insoluble in 
water, alcohol, ether, or benzine. It is the basis of a com- 
pound for rendering woven hose waterproof, the other ingre- 
dients being magnesia, black antimony, oxide of zinc, tar 
sulphur, and India-rubber. Its office is to hasten the cure. 

Carbonate of Baryta. — Known also as the mineral wither- 
ite ; has a specific gravity of 4.3. It is a white powder 
insoluble in water and alcohol. (See Barytes.) 
Carbonate of Lead. — See White Lead. 
Carbonate of Lime. — ^Very familiar under the native form 
of limestone, marble, or chalk. Specific gravity 2.7 and 2.9. ( See 
Whiting.) 

Carbonaceous Clay. — Found near Lake Albert, South 
Australia. After being boiled at a high temperature with 
caustic soda and washed with a weak solution of sulphuric 
acid, it assumes a remarkably light, spongy, elastic character. 
It is used as an absorbent, and as a substitute for cork in 
linoleum, and is suggested as an ingredient for use in connec- 
tion Avith rubber for playing-balls, etc. 

Carburet of Iron. — A name given to a mixture of graphite 
and oxide of iron. A fine black-brown powder, fairly heavy 
specifically, although variable. It makes a fair filler in com- 
pounding, being inert and strongly coherent. In packings it 
has been largely used, and also in compounds for wagon covers 
and tarpaulins before reclaimed rubber came largely into use. 
It has also been used in cements for card clothing. 

Chalk. — A white, soft, somewhat gritty substance, consist- 
ing chiefly of carbonate of lime. It is piade up of myriads of 
very small shells of marine animals long extinct. Its nature 
is earthy; that is to say, it is not easily affected by ordinary 
bodies. Acids disengage carbonic acid gas from it. Its specific 
gravity is 2.9. If heated to a red heat, carbonic acid gas 
escapes and quicklime is left behind. (See Whiting.) 



86 FILLERS IN DRY MIXING. 

Charcoal (animal). — Animal Charcoal is made from cal- 
cined bones and has the property, in a high degree, of 
absorbing odors. It is often used, therefore, in deodorizing 
rubber goods, and experimentally by chemists for filtering 
Gutta-percha dissolved in bisulphide of carbon, where a per- 
fectly clear product is desired. Its use is advised by Forster in 
Gutta-percha compounds, and by Warne, Jaques, and others 
for packings to withstand heat. (See Boneblack.) 

Charcoal (vegetable). — This is a popular term for the 
coal produced by the charring of wood. There are many mate- 
rials which are really Charcoals, such as animal charcoal just 
quoted, carbon, coke, graphite, and wood Charcoal. All of 
these are practically the same in their pure states, being almost 
wholly carbon. Wood charcoal, which is what is meant in rub- 
ber compounding by vegetable Charcoal, consists of carbon, 
hydrogen, and oxygen, the last two being in the proportion to 
form water. As it retains the form of the wood from which it 
is made, it is powdered before use. It is black and brittle, in- 
soluble in water, infusible, and non-volatile in the most intense 
heat. It has the power of condensing gases and destroying 
bad smells. Charcoal may or may not be a bad conductor of 
heat and a good conductor of electricity, these properties de- 
pending upon the wood from which it is made. Technically, 
it is divided into hard wood charcoal and soft wood charcoal. 
Its composition at ordinary temperatures is about as follows: 
Carbon 85 per cent., water 12 per cent., ash 3 per cent. It is 
used in rubber compounding in certain vulcanite varnishes and 
in certain insulated wire compounds. For this latter use, 
willow Charcoal is preferable, as it is a decided non-conductor. 
It has also been used in sponge rubber, with the idea that it 
acts as a preservative in a compound which is very likely to be 
short-lived. One curious use for it, a possible and valuable one, 
was in the attempted manufacture of cop tubes from Gutta- 
percha and Charcoal. Macintosh also used large quantities 
of ground charcoal in place of lampblack in some of his com- 
pounds. A French substitute for vulcanite paints or lacquers 
is made of 10 pounds of bitumen, 15 parts of Charcoal, and a 
little linseed oil, mixed by heating. 



CHINA CLAY— CORUNDUM. 87 

China Clay. — See Kaolin. 

CoMPO. — A name for a composition used in rubber manu- 
facture in the United States years ago, but not in use now. 
The name, however, clings to two compounds sold by an 
English chemical house for use in rubber work. They are of 
a secret nature. No. i is used in the manufacture of oil-resist- 
ing valves and in tubing for chemical factories, in the propor- 
tion of 30 pounds of Compo to 10 pounds of rubber. No. 2 is 
used for soles for tennis shoes and in mechanical goods, in the 
proportion of 25 pounds of Compo to 10 pounds of rubber. 

Cornwall Clay. — See Kaolin. 

CoRKj in granulated or powdered form, has long been a 
favorite ingredient in rubber compounding. Not that it is used 
in any such measure as whiting or barytes, but many mills 
have used it, and a few in large proportions. Used in connec- 
tion with India-rubber and Gutta-percha, it has been the 
subject of some fifty patents. Its largest use, perhaps, was in 
the manufacture of Kamptulicon, where India-rubber is used 
as a binding material, and in linoleum, where oxidized oils are 
used in place of rubber. It was also used in what was known 
as leather rubber, in which palm oil distillate, a little India- 
rubber, and a good deal of granulated cork were used. At 
one time it was also compounded with rubber and made up 
into a waterproof felt for hats. It also went into compounds 
to resist heat, into cricket balls, and into golf balls, where it 
was compounded with Gutta-percha and enough metal filings 
added to give the necessary weight. A rubber blanket used in 
special manufacture also had its surface covered with granu- 
lated Cork as an absorbent material. In some cases the Cork 
was charred and roasted to remove what resinous matter 
might be in it, while in others resinous matter was removed 
by boiling in alcohol. As is generally known, Cork is the bark 
of the cork oak, a native of the south of Europe and north of 
Africa. The chief supplies come from Spain and Portugal. 
Cork is the basis of the fine black known as Spanish black, 
which is made by burning the refuse in close vessels. 

Corundum. — A mineral which is nearly pure alumina, yet 
of great specific gravity, and of exceeding hardness, being 



88 FILLERS IN DRY MIXING. 

inferior, in this respect, only to the diamond. Emery (which see), 
so largely used as a polishing substance, is a variety of Corun- 
dum. 

DiATOMACEOus Earth. — See Infusorial Earth. 

Electric Facing. — See Farina. 

Emery. — The average composition of Emery may be taken 
as alumina 82, oxide of iron 10, silica 6, lime i^. Its specific 
gravity is about 3.8 to 4. It is prepared by breaking the stone 
at first into lumps about the size of a hen's eg^, then running it 
through stamps, and crushing it to powder. It is then sifted to 
various degrees of fineness, and graded according to the meshes 
of the sieve. Emery is next in hardness to diamond dust and 
crystalline corundum, and it is used chiefly as an abrading agent. 
Prior to the invention of vulcanite, emery wheels were made by 
mixing clay and emery in suitable mounds, and vitrifying them 
like common earthenware. In rubber mills it is chiefly used in 
the manufacture of what are known as vulcanite emery wheels. 
It is also used in grinding and sharpening compounds, as hones 
and strops. (See also' Alumina and Corundum.) A certain 
amount of it also gives the desired surface to rubber blackboards. 

Farina. — This is sometimes used in small quantities in 
unusual mixtures as a compound, but has little value, as there are 
many better substitutes for it. A practical use for it, however, 
is the brushing of a rubber surface with it before vulcanization, 
when it is necessary to have printing or stamping done upon that 
surface afterwards. Farina is made largely of potatoes, another 
name for it being Potato Starch. The process consists simply of 
crushing, sifting, washing, bleaching, and grinding, which is 
repeated three times, and each time the starch granules separate 
and are collected. Potato Starch will be remembered by rubber 
manufacturers as the material which the gossamer makers used 
successfully for a number of years in the production of the "elec- 
tric" or "corruscus" finish. Bone ash is used sometimes in the 
place of Farina, where rubber surfaces are to be printed upon. 

Feldspar. — A name given to a group of silicates of which 
the principal ones are Orthoclase or potash, feldspar, containing 
silica, alumina, and potash, and having a specific gravity of 2.5 ; 
Albite, containing silica, alumina, and soda, specific gravity 



FIRE CLAY— FOSSIL FARINA. 89 

2.61 ; Oligoclase, containing silica, alumina, soda, and lime, 
specific gravity 2.66 ; and Anorthite, containing silica, alumina, 
and lime, with a specific gravity of 2.75. The feldspars by the 
action of the weather break down into china clay, kaolin, or 
pottery clays. Ground very fine, they have been used in the 
production of rubber enamels and lacquers. 

Fire Clay. — A kind of clay which, better than any other, 
resists the action of heat and direct flame. It is composed 
principally of silica and alumina, with traces of the alkali 
earths. The best is found in conjunction with coal, and is 
called Stourbridge clay. Its specific gravity is about 2.5, and 
its color dirty white. Mixed with vulcanized India-rubber, 
dissolved in tar oil and sulphur, it forms a compound which, 
when applied to hot joints, cures at once. 

Flint is practically pure silica and has the specific gravity 
of 2.63. The nature of the powder obtained by grinding is 
always sharp and gritty. It is unacted upon by all ordinary 
means, and with difficulty even in the laboratory of the 
chemist. Its principal use, perhaps, is in the manufacture of 
glass. Flint varies in color from yellow and brown to black. 
It has been used in erasive rubbers, although pumice stone is 
better. 

Flour of Glass. — Glass powdered and sifted through a fine 
sieve of 150 meshes to the inch. Glass varies much in its 
composition, the more common kinds containing lime, while 
the so-called flint glass contains lead. Potash and soda also 
enter into the composition of glass; hence all flour of glass 
will contain those ingredients which entered into the compo- 
sition of the glass it was obtained from. Generally speaking, 
Flour of Glass may be considered an inert substance under 
ordinary conditions, though the softer kinds are attacked 
even by boiling water. It was used by Newton and Wray in 
insulated wire compounds, and has also been used in certain 
packings. 

Flour of Phosphate. — See Phosphate of Lime. 

Fossil Farina, also called mountain milk, is an earth physic- 
ally similar to infusorial earth. It is obtained from China and con- 
sists of silica 5o|^, alumina 26^, magnesia 9, water and organic 



90 FILLERS IN DRY MIXING. 

matter 13, with traces of lime and oxide of iron. It has been used 
in rubber compounding for the production of packings and semi- 
hard valves. 

Fossil Meal. — A kind of earthy mineral, principally com- 
posed of the minute shells of very small animals long extinct. 
It is similar to infusorial earth, lime and silica entering chiefly 
into its composition. It is used for the same purposes as 
infusorial earth (which see) or silica. 

French Chalk. — This is ground and sifted talc, forming a 
white, greasy-feeling powder. Its chemical composition is 
hydrated silicate of magnesia, the water being chemically 
combined. Its specific gravity is 2. (See Talc.) 

Fuller's Earth. — A kind of clay. It is a greenish or brown- 
ish earthy, somewhat greasy-feeling, substance, having a 
shining streak when rubbed. Its composition is: Silica 70, 
oxide iron 2.5, alumina 3.5, lime 6, combined water 16, mag- 
nesia trace, phosphoric acid trace, salt 2, alkalies trace. Fuller's 
Earth is found in extensive deposits in England, where its 
annual consumption at one time exceeded 2,000 tons, chiefly 
in the woolen manufacture, for fulling cloth. Its specific 
gravity is from 1.8 to 2.2. It is used in rubber compounding 
for about the same purposes as infusorial earth, and is also 
used in the manufacture of rubber type. 

Graphite. — See Plumbago. 

Gypsum. — See Sulphate of Lime. 

Infusorial Earth. — This is obtained usually from deposits 
at the bottom of inland waters, and consists of the minute 
siliceous remains of infusoria or microscopical animals. It is 
known also as fossil flour, mountain flour, and infusorial 
flour. The largest deposits, in the form of a fine white or 
pinkish powder, are found in Nova Scotia and in Germany. 
This earth is a wonderful non-conductor of heat, and, in 
connection with asbestos, is used in the manufacture of boiler 
coverings. It is used also in small proportions in various 
rubber compounds, where it increases both strength and 
resiliency, though if used in excess it makes a very hard com- 
pound. The best grades are wholly free from vegetable matter, 
are nearly pure silica, and perfectly indifferent to corrosive 



IRON PYRITES— LIME. 91 

substances. Under the name of diatomaceous silica it is used 
in a formula for elastic valve packing, patented by A. B. Jen- 
kins, United States. This packing is described as practically- 
indestructible in steam or water, oils, acids, etc. Specific 
gravity, 1.66 to 1.95. 

Iron Pyrites. — A natural sulphuret of iron, commonly of a 
bright, brass-yellow color ; a very plentiful mineral often mistaken 
for gold. It is used in the manufacture of sulphuric acid, 
while sulphur is also obtained from it by sublimation. It was 
used by Warne, Fanshaw, and others, in the manufacture of 
packings to resist a high degree of heat. The sulphur in Iron 
Pyrites has also been used in vulcanization. Warne, in one of 
his heat-resisting packings, patented the use of Iron Pyrites, 
and, in the compound that he gives as an example, leaves out 
the whole or a portion of the sulphur usually employed. (See 
Vulcanization.) 

Kaolin. — A white clay largely used in the manufacture of 
porcelain. It is a hydrated silicate of alumina. 

Kermes. — A brownish red form of sulphide of antimony, 
artificially prepared by boiling in carbonate of soda. If left 
to itself the solution will partly deposit a very fine powder of 
Kermes, while the clear solution may be further treated with 
a weak acid to obtain the remainder. Kermes will not vul- 
canize rubber without the addition of sulphur. Its specific 
gravity is about 4.5. Its compostion is 28 per cent, sulphur 
and y2 per cent, antimony. It is rarely used in rubber com- 
pounding. 

Lime. — The oxide of the metal calcium. It is commonly 
known in two states, viz. : Quick Lime, which is the pure OxidCj 
and Slaked Lime, which is the hydrated oxide mixed with some 
carbonate. Quick Lime is a white solid substance of specific 
gravity 3.2. It is not stable, taking up water and carbonic acid 
from the air and breaking down into a fine white powder, usually 
called air-slaked lime. Its power of absorbing water has caused 
it to be favorably used in drying operations, while the insoluble 
compounds it forms with various oils have led to its being con- 
sidered as a drier, although this action is not properly to be called 
one of drying. Lime, air-slaked, is used in rubber work, where 



92 FILLERS IN DRY MIXING. 

there may be a little moisture in a compound, which it readily 
neutralizes. It is also used in soft cements in connection with 
tallow and India-rubber, but only where the rubber has been 
melted and the cement is of the non-drying variety. In composi- 
tions like that of Sorel's, Lime is introduced to effect a combina- 
tion between resin acids found in the resin and resin oil. Excess 
of Lime in India-rubber is injurious, because it renders the com- 
pound too open, thus inducing oxidation. When used in small 
quantities, aside from its effect upon moisture, it combines 
with free sulphur and modifies its continued action upon the 
rubber. It must be remembered, however, that lime dimin- 
ishes the resiliency of India-rubber, while it increases the hard- 
ness of both hard and soft rubber. It may be used in small 
quantities in insulated wire, and in a measure assists the in- 
sulating capacity of the rubber. Calcium carbonate, in con- 
nection with colcothar and methyl alcohol, is used as a com- 
pound for cleansing vulcanite. Rubber also cures quicker 
when compounded with lime. 

Litharge. — One of the oxides of the lead, known as the 
monoxide. When pure its specific gravity is 9.36. Commercial 
litharge often contains carbonic acid gas and water taken up 
from the air. These may be removed by strong heating. It 
has a peculiar property, the nature of which is yet a debated 
question, by virtue of which it renders oil more easily oxidized, 
or, as it is commonly called, rendered dry. There is no reason to 
suppose that this action is available with caoutchouc. The 
best Litharge is made from pig lead, which is placed in a rever- 
beratory furnace and exposed to a current of air. which burns 
it to an oxide. It has been noted in rubber factories that 
certain men seem specially sensitive to the effects of Litharge, 
often developing serious symptoms of lead poisoning. Per- 
sons who show any symptoms should pay scrupulous attention 
to personal cleanliness. It is said that such persons have been 
cured by taking them out of the mixing room entirely, and 
putting them to work on vulcanizers, particularly where they 
open and handle the goods from the finished heat, the theory 
being that the sulphur fumes neutralize the effects of the 
lead. Possibly there is a grain of wisdom in this, for the 



LITHOPHONE— MAGNESIA. 93 

old fashioned treatment for lead poisoning was sulphur baths 
and the drinking of water aciduated with sulphuric acid or the 
acid of sulphate of magnesia. Litharge is not only a valuable 
filler for rubber, but has the faculty of hastening vulcanization 
in a marked degree. All dry heat goods depend upon it, and 
in mold work and general mechanical goods it is used when- 
ever possible. Of course, it is generally available for dark or 
black effects only. 

LiTHOPHONE. — See Colors. 

LiTHARGRiTE. — A Substitute for litharge, made of a mixture 
of pulverized and calcined magnesia and oxide of lead. 

Magnesia. — A white dry powder which, when mixed with 
water, forms a hard compact mass like marble. Its specific gravity 
is 3.65. It is earthy in its nature, having no taste, but producing a 
sense of dryness in the mouth owing to its absorption of the water 
therein. It is frequently called calcined magnesia from the method 
of preparation by burning magnesia alba. Its use in rubber is to 
increase its toughness and resiliency, which it does to a marked 
degree when used in moderation. Magnesia is also used in 
the production of compounds like balenite, its use in hard rubber 
compounds being to increase resiliency as well as hardness. A 
very small quantity of it is also used in compounds for insulated 
wire, where it is said to increase the insulating qualities of rub- 
ber. Carbonate of magnesia occurs native in the mineral mag- 
nesite and, in connection with carbonate of lime, as dolomite. 

There exist two kinds of calcined Magnesia: the heavy and 
the light calcined. Heavy calcined Magnesia is produced by cal- 
cining heavy carbonate of Magnesia, which carbonate is won by 
precipitation of hot Magnesia solutions by hot solutions of soda. 
The light calcined Magnesia is produced by calcining the light 
carbonate of Magnesia, and this light carbonate is the precipita- 
tion product of Magnesia solution together with soda solutions, 
both carefully cooled. The difference between kinds of calcined 
Magnesia concerns only the structure, so that light calcined Mag- 
nesia in a dry state seems to have a very big volume, but if the 
air bladders are driven away and the pores of the material filled 
by introducing the light Magnesia into liquids, it is easily to be 
seen that the big volume cannot have the expected effect, if light 



94 FILLERS IN DRY MIXING. 

calcined Magnesia is kneaded together with India-rubber on the 
mixing rollers. The vulcanization of India-rubber can easily be 
accelerated by addition of calcined Magnesia. Such an addition 
is often necessary with soft rubbers in open steam cured 
compounds. Rubbers with a high amount of resins, such as 
Guayule, Cameroons, Assam, Borneo, etc., usually give better 
results if compounded with appropriate additions of calcined 
magnesia. 

Manganese. — A metal of the iron group; gray or reddish 
white in color, and must be kept under rock oil or in well-sealed 
vessels, being easily destroyed by the air. Its specific gravity is 
7.2. Manganese is obtained artificially as a black powder, by 
exposing the peroxide to prolonged heat. When ignited it is 
converted into red oxide, which corresponds to the black oxide of 
iron. The black oxide of Manganese of commerce is the peroxide. 
Oxides of Manganese have a destructive effect on rubber and 
blacks that contain this, as they sometimes do, are to be avoided. 
Managnese is used in connection with pitch, turpentine, and 
Gutta-percha for making Brandt's cement. 

Marble Flour. — This is the finely ground chips of white 
marble, and is composed almost wholly of carbonate of lime. It 
is a heavy inert powder, often used in rubber compounding as a 
substitute for barytes. It has also been used to some extent in 
hard rubber, and in the manufacture of hones. 

Massisot. — An oxide of lead, dull red orange in color. A 
higher degree of oxidation turns this into a product called 
Minium, which is its purest state. It is often used in rubber com- 
pounds, acting practically like litharge. 

Mica is the name given to a group of complex silicates con- 
taining aluminum and potassium, generally with magnesium, but 
rarely with lime. Their specific gravity ranges from 2.8 to 3.2, 
while their color varies greatly. Ground mica is simply one or 
other of these micas reduced to powder. It is used in rubber 
compounding chiefly for insulating purposes. It is handled as a 
cement, compounded with rubber, and cut with benzine, or may be 
mixed dry on the grinder. It is also used in fireproof coverings 
in connection with rubber, and it is said that for a semi-hard re- 
sult that is to come in contact with hot water, rubber and Mica 



MINERAL WOOL— OXIDE OF ANTIMONY. 95 

forms the best compound. Mica in a state of a very fine pow- 
der is also known as "cat's gold" or "cat's silver." 

Mineral Wool. — Produced by sending blasts of steam 
through molten slag, which reduces the fluid metal to a fiber 
similar to the fused glass that is spun into glass silk. Natural 
mineral wool, such as is found in the Hawaiian Islands, is very 
brittle, but the artificial has considerable toughness. It is also 
known as slag wool, or silicate cotton. It appears in light fleecy 
masses, and at a distance looks like fine cotton batting. It is very 
cheap, but is easily affected by weak acids, and should be kept 
away from a moist atmosphere. It has not been largely used in 
rubber work as yet, but Lascelles-Scott strongly advises its use, 
giving as reasons its cheapness and its physical fitness. The sul- 
phides present in it also assist in vulcanization. 

Minium. — One of the oxides of lead, known also as Red 
Lead (w^hich see). It is a scarlet crystalline and granular powder 
having a specific gravity of 8.6 to 9.1. On heating, it temporarily 
changes color to violet and black, but returns again to the scarlet 
on cooling. It is adulterated with oxide of iron and brick dust. 

Mountain Flour. — See Infusorial Earth. 

Orange Mineral. — A red lead made from carbonate of 
lead, while red lead is made from litharge. As a general rule, it 
contains some lead carbonate. It differs from red lead in color, 
in that it is more orange red, and more brilliant. The reason 
for this difference is that it is less crystalline, its particles being 
much finer than those of red lead. The pigment is also more 
bulky and much smoother. It is used in finer grades of dark 
rubber, to assist the cure and impart resiliency. 

Oxide of Aluminum. — See Alumina. 

Ossein. — A light powder made from specially treated bone. 
Said not to be affected by acids. Is not affected by heat and is not 
hygroscopic. Preparation patented in England by J. F. Hunter. 

Oxide of Antimony. — There are really three of these 
oxides. The trioxide, one most useful in the arts, is a snow- 
white powder of the specific gravity of 5.2. It may be obtained 
by treating stibnite or, better still, powdered antimony metal with 
nitric acid, in a current of air sufficient to carry off the copious 
fumes arising during the operation, or by treating the chloride of 



96 FILLERS IN DRY MIXING. 

antimony with cold water for several days. A mixture of the 
trioxide with a small percentage of the insoluble peroxide may 
be obtained by melting antimony in a cast iron retort fitted with 
nozzles, through which air may be blown so as to bubble through 
the melted metal. Dense white fumes arise, which may be con- 
densed in suitable chambers into a snow-white powder. This is 
used in coloring dental vulcanite. 

Oxide of Gold. — As a matter of curiosity it may be noted 
that this is the most costly ingredient suggested for rubber com- 
pounding. It occurs in two forms — the protoxide, a dark green 
or bluish violet powder, and the teroxide, a brown powder. The 
use of the protoxide was patented by Ninck. For dental vulcan- 
ite it is doubtful if either form of the oxide could be used, even 
if the price were so low as to bring it within reach. Another 
formula calls for the mechanical admixture of gold leaf, which 
is practicable — if one possesses the gold. 

Oxide of Lead. — See Minium and Litharge. 

Oxide of Tin. — The article most frequently used in the arts 
is the dioxide. This is a white water-free powder, of the specific 
gravity of 6.7, insoluble in acids and such solvents as naphtha, 
petroleum, etc. It is infusible, except at a very high temperature, 
and is tasteless and inodorous. What is known as French Oxide 
of Tin is simply a carefully prepared and purified form of the 
dioxide. It is rarely used in rubber work, although Newton 
recommends it for a basic ingredient in rubber type. The other 
oxides of tin are at present merely of chemical interest. 

Oxide of Zinc. — See Colors. 

OxYCHLORiDE OF Lead. — There are several oxychlorides of 
lead. The substance once known as Turner's Yellow and another 
known as Carsel Yellow were both of this composition. More 
recently a white compound has been prepared, which, from its 
covering power, has been used largely as a paint. Tarpaulin 
compounds consisting of India-rubber, coal tar, and pitch are 
treated with Oxychloride of Lead for surface drying, in lieu of 
vulcanization. 

Pagodite. — A mineral resembling steatite or soapstone. Its 
name comes from its having been used in the East as a material 
for carving miniature temples or pagodas from, as it is soft 



PARIS WHITE— PHOSPHORUS. 97 

enough to be cut with a knife. Its specific gravity is about the 
same as that of soapstone, and its color greenish white. (See 
AgalmatoHte.) 

Paris White. — This has exactly the same composition as 
Whiting, but is a much harder and more compact form of English 
chalk, and therefore has greater density. Spanish White is a 
coarser variety of the same material. Its uses are practically the 
same as those of whiting. 

Petrifite. — A white powder composed of twO' inexpensive 
but secret substances. When mixed with water it solidifies 
quickly, and is an excellent binding substance. Mixed with 
marble dust, it is sometimes melted and cast upon glass or other 
smooth surfaces, and makes an excellent table-top in place of the 
zinc tables used in many rubber factories. As it is perfectly 
impervious to ordinary solvents, neither cement nor India-rubber 
sticks to it. It is manufactured in England. 

Peroxide of Lead, — ^The highest oxide of lead — a dark 
brown powder with a specific gravity of about 9. It is easily 
decomposed, and from this characteristic it has a strong oxidizing 
action. Exposed to sunlight or to heat, it yields oxygen and 
passes intO' the lower oxide known as Red Lead. Its oxidizing 
properties make it a questionable ingredient in compounding rub- 
ber, although certain formulas call for its presence. 

Peroxide of Manganese. — Another name for Black Oxide 
of Manganese, which is a black powder having a specific gravity 
of 4.8. It is not readily acted on in ordinary ways, being un- 
changed by heat short of bright red. It is insoluble in the ordinary 
hydrocarbon solvents. Solvent naphtha was treated with Perox- 
ide of Manganese by Humphry to free it from water. (See 
Manganese.) 

Phosphate of Lime. — The chief constituent of animal 
bones, forming the bulk of the ashes of the same when burnt. It 
is a white powder, and when in crystalline mineral form, it has a 
specific gravity of 3.18. It is insoluble in ether, alcohol, or the 
benzine class of solvents. As it occurs naturally it is known as 
flour of phosphate and is used in part as a substitute for whiting. 
Bone ash made from animal charcoal is used in the same way. 

Phosphorus. — A non-metallic element or metalloid, although 



98 FILLERS IN DRY MIXING. 

in its combining relation it is more closely connected with arsenic 
and antimony than with any members of the sulphur group. It 
is found ordinarily in two states — the ordinary Phosphorus and 
the red variety. Ordinary phosphorus is an almost colorless or 
faintly yellow solid substance, somewhat resembling wax, and 
giving off a disagreeable odor. It fuses at 111.5° F. into a color- 
less fluid. Heated in the air to about 140° F., it catches fire and 
burns with a bright white flame. It dissolves freely in benzol, 
bisulphide of carbon, and in many oils. Red Phosphorus is an 
amorphous powder of a deep red color, with no odor, and may 
be heated to nearly 500° F. without fusing. Its specific gravity is 
2.10. It does not take fire when rubbed, undergoes no change on 
exposure to the air at ordinary temperatures, and is far less 
inflammable than ordinary Phosphorus. It is insoluble in sol- 
vents of the ordinary Phosphorus, and is not poisonous. Mulhol- 
land made an insulated wire compound from shellac and India- 
rubber in solution, combined with one to two per cent, of Phos- 
phorus, which he cured with chloride of sulphur. As cold-cure 
gums are of little value as insulators, his invention is of doubtful 
value. He also made a preparation of India-rubber, resin and 
tallow, and shoddy, to be applied in a fluid state where gas came 
in contact with the rubber, adding Phosphorus after his solution 
was finished, to prevent decomposition of the rubber. Duvivier 
also treated Gutta-percha with sulphide of phosphorus, claiming 
that he got an elastic result, but allowing that his compound was 
damaged by acid vapors, to neutralize which action he mixed 
carbonate of soda with it. An anti-fouling preparation of English 
origin was also made of Gutta-percha, turpentine, and a little 
Phosphorus. 

Pipe Clay. — A peculiar kind of clay containing neither iron, 
sand, nor carbonate of lime. It is a beautiful white, retaining its 
whiteness when burnt. It belongs to the group of clays. Its 
specific gravity is 2 to 2.5. It was used by Mayall in combination 
with Gutta-percha, India-rubber, zinc, shellac, and resin for insu- 
lating tape, and by Austin G. Day to absorb gases during vulcan- 
ization. 

Plaster of Paris. — This is prepared from gypsum or sul- 
phate of lime. Its properties of hardening when made into a 



PLUMBAGINE— PORTLAND CEMENT. 99 

paste with water are well known. Its chemical properties are the 
same as burnt gypsum. It is used sometimes instead of lime in 
compounding and also for making trial molds for rubber work. It 
was used in old fashioned dry heat compounds to prevent Mister- 
ing. Specific gravity, 3.2. (See Anhydrite.) 

Plumbagine. — A dark colored pigment manufactured in 
England and sold to rubber manufacturers for the production of 
valves. By its use the rubber is vulcanized and goods made which 
are said to resist successfully the action of cheap lubricants. One 
pound of Plumbagine is used to two pounds of rubber. 

Plumbago, — This sometimes is called Black Lead, though 
having no relation to lead ; it is also called Graphite. Its specific 
gravity is 2.1 to 2,2. Its color is black and shiny. It consists 
chiefly of carbon, but contains more or less alumina, silica, lime, 
iron, etc., varying from i to 47 per cent., but not chemically com- 
bined. Black Lead is a perfect conductor of electricity. It is 
more incombustible than most ingredients used in rubber com- 
pounding, and is capable of withstanding great heat. It is used 
in the rubber industry, chiefly in the manufacture of what are 
known as graphite or plumbago packings. It is a wholly inert 
substance, safe to use in connection with any compounds, and is 
not affected by heat or acids, alkalies, or corrosive substances. It 
is useful also in certain polishing compositions made with India- 
rubber as a base, German asbestos cements almost all contain a 
^ood proportion of finely powdered graphite, 

Portland Cement "was first obtained by burning the mud 
found at the mouths of several large rivers in Europe with a pro- 
portion of clay and lime. Its composition is somewhat complex, 
containing : Lime 55 to 63 per cent., silicic acid 23 to 26 per cent., 
alumina 5 to 9 per cent., and oxide of iron 2 to 6 per cent., to- 
gether with magnesia, potash, soda, sulphate of lime, clay, or 
sand in various small proportions, according to the mode of manu- 
facture. Its value as a cement depends upon the interaction of 
the lime and the silicic acid. In compounding it would have no 
chemical effects upon rubber, but might of itself become much 
hardened and thus cause mechanical injury to goods in which it 
has been introduced. As it occurs commercially, it is a gritty 
powder of a gray brown or yellow brown color. Its only use as 



100 FILLERS IN DRY MIXING. 

far as known in rubber is where it is mixed with tar oil and 
waste rubber to joint pipes containing fluids. 

Powdered Coal. — Coal consists chiefly of carbon, and is 
universally regarded as being of vegetable origin. Various coals 
differ widely in their composition and characters, running from 
the softest kinds of earths to compact and solid bodies like Parrot 
coal, which is so compact and solid that it has been made into 
boxes, inkstands, and other articles which resemble jet. The 
average specimen of coal analyses is: Carbon 82.6, hydrogen 5.6, 
oxygen 11.8. Some curious compounds of India-rubber and Coal 
have been formed. One, for instance, was a mixture in which 
two pounds of waste India-rubber in a cheap solvent was mixed 
with nearly a ton of powdered Coal, in which was a certain 
amount of clay and peat, the use being for an artificial fuel; 
another use was in the production of hard rubber. Indeed, it is 
probable that the cheapest compound in use to-day is a jet black, 
semi-hard rubber made almost wholly of powdered bituminous 
Coal in which is incorporated a very small percentage of rubber. 
Coal that is to be used in any rubber work should be submitted to 
a chemist and its sulphur and other compounds carefully deter- 
mined before use. 

Pumice Stone. — A light porous ashy stone, the product of 
volcanic action, its structure being that of a mass of porous glass. 
Its composition is a mixture of silicates of aluminum, magnesia, 
calcium, iron, potassium, and sodium, varying with the particular 
lava whence it had its origin. Its action on India-rubber will be 
quite inappreciable, chemically speaking, but its mechanical action 
will be that of a sharp cutting powder. Ground fine, it is used 
in the manufacture of erasive rubber, and is also' used compounded 
with the rubber in the manufacture of bones. Recent patents call 
for its use in certain semi-hard compounds, its presence being said 
greatly to increase their toughness. Mixed with lard oil to a 
thick paste, this has been used for polishing India-rubber. 

PuzzoLANA. — A porous lava found near Naples, used 
chiefly, when mixed with ordinary lime, in forming hydraulic 
cement. Compounded with marine glue, it is used as a varnish for 
preserving metallic articles from corrosion. 

Red Chalk. — Artificially deposited chalk colored by any 



RED LEAD—SLAKED LIME. loi 

suitable pigment — ^usually one of the red oxides of iron. (See 
Chalk.) 

Red Lead. — An oxide of the metal, which is also known as 
Minium. Prepared from pure massicot or from white lead. Its 
specific gravity is 8.6 to 9.1. A scarlet crystalline granular pow- 
der, of rather strong coloring powers. As a colorant in rubber 
work it would be unavailable, since the sulphur necessary to vul- 
canize would render it more or less black, owing to the formation 
of sulphide of lead. It is sometimes used, however, in place of 
litharge. It is also used in "hot" cements of Gutta-percha and 
for varnishes such as those made of India-rubber, linseed oil, 
etc., for covering the backs of mirrors. (See Minium, Massicot, 
and Orange Mineral.) 

Rotten Stone. — Usually considered to be the residuum of 
naturally decomposed impure limestone, and varying in composi- 
tion with its sources. That from Derbyshire, England, shows 
much alumina ; other sorts have more silica. The name is some- 
times given to "Tripoli," which is a species of infusorial earth. It 
can have no particular action on rubber, as it is very inert, but is 
used in certain packings, and was also used by Warne in insu- 
lated wire compounds. 

Selenium. — A non-metallic element or metalloid of a dark 
brown color, analagous to sulphur. It has no smell, is tasteless, 
and is a non-conductor of electricity. It occurs rarely in nature, 
being found chiefly as a selenide in combination with lead, silver, 
copper, or iron. It is the basis of a process for vulcanizing India- 
rubber. 

SiLEX. — Pure Silica. (See Flint.) 

Silica. — The oxide of the metal silicon, familiar in the 
forms of flint, quartz, etc. Its specific gravity is 2.6. It is with- 
out action on India-rubber, except mechanically speaking. It is 
used in Chapman's vulcanite enameling solution, made of India- 
rubber, sulphur and silica. (See Flint.) 

Silicate Cotton. — See Mineral Wool. 

Slag Wool. — See Mineral Wool. 

Slaked Lime. — Quick lime that has been treated with water, 
and allowed to absorb it from the air and crumbled to a fine 
powder, (See Lime.) 



102 FILLERS IN DRY MIXING. 

Slate. — A soft easily laminated earthy material, chiefly alu- 
minous in composition, and allied to the clays. Finely ground, 
it makes a good semi-hard valve of a blue gray shade. It has 
been also used in general rubber compounding. 

SoAPSTONE. — A silicate of magnesia, combined with more or 
less alumina and water. It is really a massive form of talc. In 
color it is white, reddish, or yellow, is soft and greasy to 
the touch, is easily cut, but is hard to break. Its specific 
gravity is 2.26. It is used often in the place of French talc, for 
keeping rubber surfaces from sticking together during vulcan- 
ization, and also for burying dark colored goods and holding 
them in shape while they are being cured. Used as an adulter- 
ant for rubber, it makes an excellent semi-hard compound for 
valves. It is also used as a basis compound in the manufacture 
of insulated wire. (See Talc.) 

Starch. — A vegetable substance allied closely to cellulose. 
It occurs in regular lumps, composed of granules which have a 
definite character, according to the variety of the plant they 
were taken from. When dry its specific gravity is 1.53. Com- 
mercial starch contains usually about 18 per cent, of water and, 
if kept in a damp place, will absorb 33 per cent, of water. It 
was much used formerly on solarized work. Torrefied Starch 
is obtained by roasting the common form, and is used in arti- 
ficial leather compounds. 

Stibnite. — That ore of antimony known usually as black 
antimony. (See Kermes.) 

Sublimed Lead. — Used in the rubber manufacture, it acts 
both as a filler and chemically. Its peculiar velvety fineness 
makes it mix intimately with the rubber, and gives a very fine 
finish, showing no shiny crystals on the surface. The oxide of 
lead in the Sublimed Lead will also bind free sulphur in the 
rubber. The amorphous state of the Sublimed Lead makes the 
action of the lead oxide in this much more effective than the 
action of litharge, and the result is a very smooth lively jet 
black rubber. 

Sugar of Lead. — See Acetate of Lead. 

Sulphate of Lead. — A white powder of the specific gravity 
of 6.2, insoluble in water, but readily soluble in caustic alkalies. 



SULPHATE OF LIME— WHEAT FLOUR. 103 

It is not a very stable compound. In Cooky's formula for arti- 
ficial leather, which has Gutta-percha for a base, it is used in 
connection with dextrine, magnesia, and cotton dust. 

Sulphate of Lime. — Also called Gypsum. A common min- 
eral occurring under various forms and names as alabaster, 
selenite, and gypsum earth. It is pure white in color and has 
a specific gravity of 2.33. Plaster of paris is a burnt form of 
gypsum. In the ordinary recovery of rubber by the acid pro- 
cess, whiting becomes gypsum. (See Anhydrite.) 

Sulphate of Zinc. — Also called White Vitriol. It occurs 
in the form of a transparent crystal containing about 44 per 
cent, of water of crystallization, 87 per cent, of which is not 
given up short of a red heat. Its specific gravity is about 2.03. 

Talc or French Talc is a mineral allied to mica. It is 
composed entirely of silica and magnesia, in the proportions of 
67 to 73 of silica, 30 to 35 of magnesia, and 2 to 6 of water. Its 
colors are silvery white, greenish white, and green. Talc slate 
is more like steatite and is used for similar purposes. French 
Talc is used very largely in rubber factories in all lines of work 
for preventing surfaces from sticking together, during either 
manipulation or vulcanization. It is used also sometimes for 
dusting molds to prevent the gum from sticking to the metal 
and is used largely to bury white goods and keep them in shape 
during vulcanization. It is used sometimes in compounding, 
but any great amount of it produces a stony effect. It makes, 
however, an excellent semi-hard packing. It is used further in 
compounds for soft polishing, with India-rubber as a binding 
material. 

Talite. — A white earthy material used in general rubber 
compounding. It is allied to diatomaceous earth, presumably, 
and has the same usage. Its analysis shows : Moisture 5.59, 
silica 83.9, sesquioxide of iron 1.2, alumina 2.8, oxide of man- 
ganese trace, potash trace, combined water and organic matter 
(by ignition) 6.47, loss and undetermined 0.04 — total 100. 

Tripoli. — See Rotten Stone and Infusorial Earth. 

Wheat Flour is used in making matrices for rubber stamp 
work, and sometimes as a compounding material in India- 
rubber, though this is not to be advised, as the flour is apt to 



104 FILLERS IN DRY MIXING. 

turn sour. A large and important use for it has been in the 
dusting of black goods, such as rubber coats, so as to keep 
them from sticking together, should they accidentally touch 
during dry heat of vulcanization. Wheat Flour is preferable 
to almost anything else, for the reason that it washes off after 
vulcanization, without leaving any trace in color or stain. It 
is, of course, used on the goods known as "dull finished." 

Whiting or Chalk, as it is often called, is carbonate of 
lime. It is a white earthy material of the specific gravity of 
2.7 to 2.9. It is made from English chalk, which is crushed, 
floated, and run through a filtering process, and dried in cakes, 
out of which, by a system of dry grinding and bolting, it is 
made in varying degrees of fineness. Where Whiting is kiln 
dried hastily, or under extreme heat, it is apt to become cal- 
cined, which gives it a hard, gritting feeling. Air dried Whiting 
is considered the best. Whiting is in reality a purified form of 
carbonate of calcium, of a very soft or flocculent quality. The 
finest grades are known as "gilders' " and "extra gilders'." It 
is used more generally in rubber compounding than any other 
material, except sulphur. Used moderately, it increases the 
resiliency of rubber, but adds to the hardness. It does not, 
however, produce the stony eiifect that many ingredients give. 
It is also the basis of the molds used in rubber stamp making ; 
paste being made of whiting, wheat flour, glue, and carbolic 
acid. Whiting is liable to absorb considerable quantities of 
water from the air. It is customary in many mills, therefore, 
to keep it in large bins that not only are covered but have 
steam pipes in the lower portions to drive out any moisture 
from the material. 

White Lead. — ^This is a carbonate and is a heavy white 
powder. It is unstable in color, however, as sulphur com- 
pounds, especially in the gaseous forms, easily attack it and 
blacken it by reason of the formation of sulphide of lead. Its 
specific gravity is 6.46. Sometimes it is adulterated with lead 
sulphate, chalk, carbonate, or sulphate of baryta, or pipe clay. 
The simplest test for the purity of White Lead is to heat it 
in a thin glass vessel with some very dilute pure nitric acid; 
if pure it will dissolve completely. If chalk be present it also 



UNUSUAL INGREDIENTS. 105 

will pass into the solution, in which it may be detected by the 
addition of caustic potash, throwing it down as a white cloud. 
The best carbonate of lead is made by an old-fashioned pro- 
cess, by placing metallic lead, surrounded with spent tan 
bark, in stacks, where it comes in contact with weak acetic 
acid. The heat of the bark volatilizes the acid and oxidizes 
the lead, while the acetic acid changes the oxide into acetate 
of lead, and this in turn is converted into carbonate by the 
carbonic acid given off by the heated body. This process of 
corrosion requires from six to eight weeks. There are many 
later and more rapid processes ; for instance, take either lith- 
arge or acetate of lead, and expose them to a current of 
carbonic acid gas, etc. The original "triple compound" 
patented by Goodyear consisted of India-rubber, sulphur, 
and White Lead. A White Lead known as sublimed lead is 
used very largely in the rubber manufacture. It is a fine 
white amorphous powder and imparts a decided toughness 
to rubber compounds. (See Sublimed Lead.) 

UNUSUAL INGREDIENTS IN DRY MIXING. 

It is not strictly accurate, perhaps, to say that it is unusual 
for fibers to be incorporated in rubber mixtures, for stocks 
made from unvulcanized rubber clippings have been used for 
years. Inner soles for rubber footwear and mats and molded 
articles have long been made of stocks of this kind, the fibers 
being cotton and wool, chiefly. Where wool was present 
there was oftentimes danger of blistering from the oil in the 
fiber, but this was easily gotten over by special compounding. 
In addition to the fibers already noted, silk, flax, jute and 
hemp — in fact, almost all of those in ordinary use — ^have been 
utilized, being added to the compounds to give toughness to 
them. The goods in which they are usually put are packings, 
artificial leathers, tire treads, and for wearing surfaces. 

A fiber that has attracted considerable attention for this 
work, and one for which a number of patents have been 
granted, is cocoanut fiber, which is recommended for pack- 
ings. Certain kinds of moss have also been used, as have 
sponge cuttings, peat, and wood pulp. This last-named ma- 



io6 FILLERS IN DRY MIXING. 

terial has been used both in packings and in insulated wire 
compounds. It is also the basis of a curious artificial rubber 
that appeared several years ago, under the name of Maltha, 
but is not to be confused with the product that has become 
almost universally known by that name. 

Sawdust of all kinds has also been incorporated in rubber, 
and was formerly used in making sponge rubber, until better com- 
pounds were discovered. Those who use vegetable fibers prefer 
them unbleached rather than bleached, and very often treat them 
to remove resins that may be present. A few of the many other 
vegetable substances that have been used are sugar and sugar 
charcoal and seaweed. (See Algin.) 

Animal substances are also valuable, as for instance, animal 
charcoal (which see), whalebone, which is called for in some of 
the Woodite patents, fur, tan-hair, leather fiber, Currier's skiv- 
ings, which are used in artificial leather, the white of eggs, etc. 

Under the head of earthy and metallic ingredients, almost 
anything can be used, although some metals have a bad effect on 
rubber. The unusual earthy matters are powdered fossil iron- 
stone, Wisconsin mineral, coke ashes, Stourbridge clay, powdered 
granite, salt, powdered lithographic stones, powdered oyster shells, 
powdered schist ; and in metals, steel, and all other common metal 
borings, filings, and turnings. These latter have been incorpor- 
ated in packings as a rule. One packing in particular, which has 
had a world-wide reputation, was heavily compounded with brass 
filings. 

The deodorization of rubber, and the neutralization either of 
the smell of the rubber or its solvent, has brought out also a 
curious line of ingredients. Musk, for example, has been used to 
disguise the earthy odor of Gutta-percha. Alcoholic infusions of 
sage-tea, lavender, and verbena have been used in fine goods, 
while in powdered form, ginger root, birch, orris root, sassafras, 
marshmallow root, sandal wood, and other sweet smelling ingre- 
dients have been incorporated. The leaf of the mint has also been 
mingled with copperas, and placed in dry heaters, while a more 
expensive process was that pursued by Hill, who passed a cur- 
rent of hot air over perfumes and into the heaters. It must not 
be imagined that the ideas expressed in the foregoing are 



ADHESIVE PLASTERS. 107 

unworthy of the consideration of those who make ordinary cheap 
mechanical goods, for certain of these ingredients are used to-day 
in mechanical mixtures to overcome the odors of African rubbers. 
Essential oils and gums are also used for the same purposes, 
the descriptions of which will be found under their proper 
departments. 

Medical science has also add-ed its list of ingredients to rub- 
ber compounding, chiefly in the line of adhesive plasters, where 
ingredients like dry mustard, menthol, capsicum, belladonna and 
a great variety of other medicaments are incorporated with the 
rubber. 



CHAPTER VI. 

I. SUBSTITUTES FOR INDIA-RUBBER AND GUTTA-PERCHA. 

Rubber Substitutes^ as a rule, are made from oxidized oils. 
Those used most generally are made from linseed, rapeseed, 
cottonseed, mustard, peanut, or corn oils, acted on either by 
chloride of sulphur or by sulphur boiled with the oil at a high 
temperature. Substitutes have been known nearly fifty years, 
and have been made the subjects of many patents, but only 
within the last twenty years have they come into general use. 
French manufacturers have long exported these goods ; they 
were really the first to produce them commercially. The fact 
that Europeans were unable at first to get the results with 
reclaimed rubber that were secured in the United States, led 
them to go further in their experiments with oxidized oils and 
to exploit their uses more thoroughly. The substitutes on 
the market to-day are, as a rule, white, brown, and black. 
They are often of the same specific gravity as pure India- 
rubber, so that their presence cannot be detected in rubber 
compounds by specific gravity tests. Substitutes of this type 
are easily analyzed by the expert chemists, and the results of 
such analyses are of value to rubber manufacturers. The 
table on the next page, containing analyses of typical sorts of 
substitutes, is adapted from Dr. Robert Henriques*. 

It would be a mistake to suppose that rubber substitutes 
are of no value, for they possess certain very distinct advan- 
tages not found in simple mineral adulterants nor possessed 
by the bituminous products now in use. Their value, of 
course, is where they cheapen stock without seriously injuring 
its durability or changing its texture. Among the wiser of 
the manufacturers, where substitutes are compounded with 
rubber they are used in small quantities, sometimes only 5 per 
cent, being added, and rarely is more than 25 per cent, to be 
found in a good compound. 



^Journal of the Society of Chemical Industry, igo4, Page 47. 

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no SUBSTITUTES FOR RUBBER. 

Many substitutes, made from sulphurized drying oils, 
shorten the life of goods materially, by oxidizing the rubber. 
Manufacturers have learned, however, to avoid those that 
have this fault, and are becoming more and more expert in the 
use of these goods, as they have become in the use of the 
cheaper grades of African rubber and reclaimed rubber. 

The list in the accompanying table has been made quite com- 
prehensive, not because all the substitutes described are 
deemed valuable, but rather to give a broad view of the sub- 
ject. It will be noticed that many of these gums are far out 
of the line of sulphurized oil experiments. Resins, glues, 
asphalt, cellulose, seaweed, bastard rubbers, animal substances, 
etc., have all been called upon, and some of the treatments 
have been as original as the ingredients are unusual. To the 
end that the perfect substitute may be found, and with the 
fullest appreciation that anything which suggests new experi- 
ments has its value to the manufacturer, many that otherwise 
would be ignored are given here. 

Adamanta. — The American name for a German substitute 
for India-rubber, made from linseed oil, sulphur, lime, and 
resin. It is a thick, black, gummy mass, with an odor similar 
to that of most of the sulphur oil substitutes, and showing a 
bright cleavage. It was at one time used largely in France 
and Germany, and introduced to some extent into the United 
States. Its chief use was in cheap mechanical rubber goods, 
and for insulation. 

Adhesor. — A sticky substitute used to a certain extent in 
frictions. 

Adirondackite. — A rubber substitute presumably made of 
sulpurized oil for use in proofing cloth and also an insulator. 
Invention of a chemist in New York State. 

Algin Gum. — A gluey, leathery substance, manufactured 
from seawood. It is insoluble in cold water, alcohol, ether, and 
glycerine, and combines readily with alkaline and metallic 
bases to form substances, many of which are soluble. Algin 
can be used for waterproofing compounds, as it combines 
easily with rubber, shellac, and other gums. With many 



AMBER-RESIN— BLANDITE. in 

metallic bases it forms insoluble compounds as tough as horn 
or as pliable as Gutta-percha. It is an English product. 

Amber-resin Substitute. — An English patented substitute 
made of Amber-resin dissolved in castor oil, heated with a little 
sulphur. Is treated with ozonized air after cooling. The mass 
then treated with chloride of sulphur in the presence of a 
solvent, calcium carbonate being also added. 

A. R. D. Gum. — So called because it is used as an anti-dry- 
rot compound. It is manufactured of 112 parts glue, 56 parts 
resin, 10 parts boiled linseed, and 35 parts water. In some 
cases it has also been mixed with India-rubber in general com- 
pounding. Patented by J. F. Ebner, London, England. 

Artificial Elaterite. — Made from liquid bitumen by in- 
corporating with it vegetable oils, such as cottonseed oil, palm 
oil, rapeseed oil, etc. The product is treated with the aid of heat 
and pressure, with chloride of sulphur, saltpeter, and sulphur, 
which produces an oxidization of the fatty substances. The 
result is an elastic rubber-like or leathery mass, which is soft, 
spongy, and gluey. This gum is said to be far more elastic than 
the best samples of mineral rubber, and is useful for waterproof- 
ing and insulation. Patented by W. Brierly, in England. 

Artificial Gutta-percha. — A French compound made of 
50 parts copal, 15 parts sulphur, 30 parts turpentine, and 60 
parts petroleum. While mixing the heat reaches 100° C. ; it 
is then cooled to 35° C. Then there is added a solution of 3 
parts caseine, in weak ammonia, and a little methylene, and 
reheated to 120° C. It is then boiled with a 15 or 20 per cent, 
solution of tannin, and 15 parts ammonia. After several hours' 
l)oiling it is washed and cooled. 

Borcherdt's compound for dolls' heads consists of 5 pounds 
glue, 10 pounds sugar, 2^ pounds glycerine, 3 pounds Perry's 
white. 

Black German Substitute. — Made of boiled linseed oil and 
sulphur, together with resinate of lime. This gum is similar to 
Adamanta, and has been practically driven out of the market 
by lighter substitutes. 

Blandite. — An artificial India-rubber invented by Dr. A. L. 
Blandy, of London. It is fairly elastic, stretching to about 



112 SUBSTITUTES FOR RUBBER. 

twice its length, and returning readily. It is very pliable and 
does not show signs of cracking when bent. It is vulcanized 
like ordinary rubber, and can be molded into any form desired. 
Coated on cloth, it strongly resembles leather. It is water- 
proof, and is used for gas tubing, mats, etc. In its crude form, 
it is a liquid mass resembling molasses. Dr. Blandy's patent 
describes the compound as made preferably of linseed oil 
which has been reduced by oxidation; then lo per cent, of bisul- 
phide of carbon, to which has been added lo per cent, of 
chloride of sulphur, is mingled with the oil, and brought by 
gentle heating to the desired consistency. Trinidad asphalt, 
cleansed and reduced to powder, is combined under the heat 
in the proportion of 3 parts to i of oil. Care must be taken to 
avoid fire in heating. These proportions are gradually 
brought, by heat and stirring, to a liquid or thin state, and 
when in this condition it must be poured upon a wet, cold 
surface, and thus cast into sheets, convenient for subsequent 
mixings. 

Caoutchene. — A French substitute consisting of 100 parts 
sun-flowerseed oil, 25 parts chloride of sulphur, and exposed to 
air ten days, when it becomes yellow and elastic. To this is 
added Matesite, a Madagascar gum, and then Isoprene is 
added. 

Carrol Gum. — A well-known sulphur oil substitute used in 
the United States. In smell it has all of the characteristics 
of the sulphurized oil products. It is produced usually in 
granular form, and is very black. 

Carbo-nite. — A material used for soft insulation, the basis 
of the product being cottonseed oil. 

Cereal Rubber. — Wheat treated with ptyalin. The inven- 
tion of William Threnfall Carr, of England. It is a gluey 
product which after it comes from the so-called vulcanizing 
press is said to be both plastic and waterproof. 

Chicle Substitute. — A specially prepared gum-carbo or 
cottonseed oil substitute. Said to be very largely used by 
manufacturers of chewing gum. (See Gum-carbo.) 

Chinese Wood Oil Substitute. — A German invention 



CHRISTIA GUM—ELASTEINE. 113 

F. for eight hours, then vulcanize with chloride of sulphur. 

Christia Gum. — An English substitute for Gutta-percha or 
India-rubber, used as a surgical dressing. It is said to be 
composed of hemp fibers, so treated as to be impervious to 
both alcohol and water. Dieterich analyzed a sample of the 
product, and said that the fibers were sulphite wood pulp, and 
that the coating was made from chrome gelatine treated with 
glycerine, or the well known compound of glue, glycerine, 
and bichromate of potassium. 

CoN-cuRRENT RuBBER. — Invention of Julius Nagel, of New 
York. A secret compound, the basis of which is linseed oil 
and resins. 

CoRKALiNE is made of glue, glycerine, ground cork, and 
chromic and tannic acids. It is of English derivation and is 
used as a substitute in mat work. 

Corn Oil Substitute. — A sulphurized oil substitute similar 
to that made from oxidized linseed or rapeseed oils, manu- 
factured from corn or maize oil. It is the cheapest oil sub- 
stitute that has yet been put on the market. It is made in two 
colors, brown and straw color, and is used in large quantities 
in mechanical goods, and in proofing. A good example of 
this type of substitute is that known on the market as "Kom- 
moid." 

Dankwerth's Russian Substitute. — This is said to be a 
perfect substitute for both Gutta-percha and India-rubber, 
and is used for covering telegraph cables. High temperatures 
do not affect it. It is made of i part by weight of the mixture 
of equal parts of wood tar, oil, and coal tar oil, with 2 parts 
of hemp oil heated until the mass is of the right consistency. 
Then 1-3 part by weight of boiled linseed oil is added. To 
this is added a little ozocerite and some spermaceti. It is 
then heated again, and finally a little sulphur is added. 

Doebrich's Compound for dolls' heads consists of i pound 
glue, ^ pound glycerine, | pound sugar, and i tablespoonful 
pulverized flour, with a little albumen and coloring matter. 

Elasteine. — ^An elastic substance produced through the 
treatment of certain resins. Solid and semi-solid copal resins 
are treated with oleic acid (found in stearine works), which 



114 SUBSTITUTES FOR RUBBER. 

entirely dissolves them. The product of the solution is soluble 
in spirits of turpentine and in oil. This solution of gums in 
oleic acid gives an opportunity to produce materials that have 
sometimes the elasticity and the consistency of India-rubber. 
The inventor advises their use in insulating wire and in 
various kinds of proofing. It is of French origin, and patented 
by M. Louis Riviere. 

Elasticite. — ^Trade name for an American corn oil sub- 
stitute. 

Elastite. — A brown rubber substitute of German origin of 
the sulphur oil type. 

Elastic Glue. — A mixture of dry glue and glycerine in 
equal parts, by weight. As little water should be used as 
possible in its manufacture. It is used for elastic figures, 
galvano-plastic molds, etc. It is not waterproof, nor will it 
stand a high degree of heat. 

Elaterite. — See Artificial Elaterite. 

Euphorbia Rubber. — J. G. Boles reduced Euphorbia gum to 
a fine powder and, after drying carefully at a low temperature, 
put it in solution and finally hardened it by mixing it with 
earthy matters and shellac. The same gum before that he 
mixed with a preparation of rubber and cured it, forming a 
kind of vulcanite. 

Fayolles' Substitute. — A French substitute for water 
proofing, made as follows : i part sulphuric acid, i part gly- 
cerine, i-| parts Formalin, i part phenol. 

Fenton's Artificial India-rubber. — Manufactured from 
linseed or similar oils, mixed with tar, pitch, or other forms of 
pyroligneous acid, the mixture being placed in a bath of 
diluted nitric acid, and allowed to remain for maceration until, 
by the action of the bath upon the compound, the whole is 
coagulated into a tough, elastic magna. The black "Fenton" 
contains as a coloring matter a small quantity of plumbago or 
black carbonate of iron. The gum is patented by Ferrar 
Fenton, London, England. In his specification he modifies it 
by taking the artificial gum described, and placing it in a bath 
composed of a solution of sugar of lead, oxide of zinc, salt- 
peter, or some other form of nitrate, and, if high flexibility is 



FIG JUICE— GUM FIBRINE. 115 

desired, adds 5 to 10 per cent, to copal gum and nitric acid 
diluted with water. These solutions are used one at a time, the 
proportion being 5 per cent, of sugar of lead, or, for greater 
hardness, 5 to 7^ per cent, of saltpeter to the weight of the 
magna. Before vulcanizing, the substances are washed in an 
alkaline solution to remove acid. Fenton rubber is said to have 
been subjected to 320° F. for fifteen minutes, the only result 
being to increase its elasticity. 

Fig Juice Proofing. — A French composition made up of fig 
juice, Brazilian tapioca, and pearl moss, together with vulcanized 
rubber. Used as a preservative and proofing compound. 

FiRMUS. — An English rubber substitute presumably of the 
sulphur oil order. 

Franklin Substitute. — A mixture of coal tar and boracic 
acid dissolved in alcohol. Boiled and oxidized. 

French Gutta-percha. — This gum is made by boiling the 
outer bark of the birch tree in water. The result is a fluid, 
which is very black, and which becomes compact and solid on 
cooling. It has been claimed that it possesses all of the good 
properties of Gutta-percha, and that in addition it does not 
oxidize when exposed to the air. Its application for industrial 
purposes has been patented. 

Grape Rubber. — A high grade or artificial rubber, produced 
from the skins and seeds of grapes from which wine has been 
extracted by pressure. Small samples manufactured in the 
laboratory are said to be almost identical with pure rubber. 
It has been impossible so far to make the material on a large 
scale economically and, therefore, none of the gum is on the 
market. 

Griscom's Substitute. — A substitute composed of equal 
parts of animal fat, candle tar, and a residual product from 
petroleum together with sulphur in proportions of from 2 to 
8 per cent, of the mass. 

GuM-CARBO. — Substitute made from cottonseed oil. Used 
in general rubber compounding. 

Gum Fibrine is made of paper rags, treated with liquid car- 
bonic acid, mixed with resin and gum benzoin and castor oil, 
dissolved in methylated alcohol. It is an English compound. 



ii6 SUBSTITUTES FOR RUBBER. 

GuTTALiNE. — A substitute for India-rubber and Gutta- 
percha, manufactured as follows : To Manila gum tempered 
with benzine is added 5 per cent, of Auvergne bitumen, also 
mixed with benzine. Then add 5 per cent, of resin oil, and 
allow 48 to 86 hours to pass between treatments. The pro- 
duct obtained is similar to India-rubber. If it be too fluid, the 
addition of 4 per cent, of sulphur dissolved in bisulphide of 
carbon will act as a remedy. 

Gutta-percha Substitute. — Formula: 2 parts paraffine, 2 
parts pitch, 2^ parts Chinese wood oil, i.i parts chloride of 
sulphur, 0.1 flowers of sulphur. Heat to 100° C. for one hour. 

Halcox. — A so-called artificial rubber, the invention of H. 
B. Cox, of Hartford, Connnecticut. Claimed to be almost 
identical with crude rubber, but much cheaper. 

Hydrocarbon Rubber. — The invention of Eugene Turpin, 
of England. Made by heating a vegetable oil, oxidizing by air 
current, adding 25 per cent, by weight of resin, 25 per cent, pow- 
dered sulphur, 5 per cent, spirits of turpentine, and i to 2 per 
cent, carbon chloride. 

Hydrolaine. — One of the original waterproof fabrics made 
by means of India-rubber dissolved in spirits of turpentine and 
spirits of wine in equal quantities, and deodorized by oil of worm- 
wood. 

Insulite. — A preparation made of wood or vegetable fiber, 
finely ground and dessicated, and saturated with a mixture con- 
sisting of melted asphalt, incorporated with substances of the 
resin type, with or without substances of the paraffine or anthra- 
cine types. The products resulting are used as substitutes for 
India-rubber, particularly in insulation. Patented by Alfred H. 
Huth, London. 

Jones's Substitute. — An English substitute made of treated 
psuedo gums. Marketed by the Rubber Substitutes Syndicate, 
Limited, of London. 

Jungbluth's Compound. — Calcium carbonate 75 per cent. 
Trinidad asphalt 20 per cent., Selenite 5 per cent. In place of 
Trinidad Asphalt, neutralite, an asphaltic material made in Berlin 
is sometimes used. 

Kelgum. — A linseed oil preparation manufactured in the 



KELGUM—LINOXIN. 117 

following way: First, boiling linseed oil in a nitric acid bath 
until it reaches a gum-like condition; second, subjecting the 
gum to a bath for the removal of the acid; third, cutting the 
gum in a solvent bath; fourth, disintegrating the gum with 
the solvent ; fifth, grinding the disintegrated mass ; sixth, boil- 
ing the material; seventh, subjecting the same to another 
boiling, and adding a drier. Used in proofing compounds. 
Invented by Henry Kellog, United States. 

Kerite, — A compound of vegetable oils, coal tar, bitumen, 
and sulphur, to which are added sometimes a little camphor 
and various waxes. Occasionally sulphide of antimony is 
used in place of sulphur. Vegetable astringents, such as 
tannin, the extract of oak bark, etc., are also used in small 
quantities to impart toughness, Kerite is the invention of 
Austin G. Day, and has been used largely for the manufacture 
of a covering for insulated wire. A later p'atent taken out by 
W. R. Brixey, changes the original Kerite compound some- 
what. Cottonseed oil is eliminated and talc added. The 
later compound is as follows : 

MIXTURE FOR l8o POUNDS. 

Coal tar 25 pounds. 

Asphalt 15 pounds. 

Heat together to 350° F. for i hour; then add — 

Linseed oil 70 pounds. 

Heat again to 350° F. for 7 hours ; let stand over 
night; heat up to 240° F., and add — 

Sulphur 10 pounds. 

Heat up to 320° F. in ^ hour and add — 

Sulphur 4 pounds. 

Heat again to 300° F. and add — 

Talc 56 pounds. 

Keep at same temperature i to I hour, when vul- 
canization will have taken place, and the mix- 
ture can be poured into molds or allowed 
to cool in mass. 

KoMMOiD. — See Corn Oil Substitute. 

LicoNiTE, produced in Holland, is described as a mixture 
of bitumen and various oils, without India-rubber or Gutta- 
percha, elastic and tough, and is claimed to be unaffected by 
water, dilute acids, and alkalies, and neither flows nor cracks 
in ordinary temperatures. 

LiNOXiN. — An insoluble oxy-compound produced by the oxi- 
dation of certain drying oils boiled in acetone or acetic acid, 



ii8 SUBSTITUTES FOR RUBBER. 

from which is produced an elastic mass similar to India-rubber. 
Of French origin. 

Lugo Rubber. — An artificial oxidized oil substitute that 
originated with Dr. Lugo, a German chemist, who introduced 
it into the United States, where it once had a large sale. It 
was black, of about the same specific gravity as India-rubber, 
and made, in connection with rubber, excellent mold work. 
It is not now on the market. 

Lugo. — A rubber substitute patented in England, made by 
heating a mixture of oxidized oil and rubber to a temperature 
at which the rubber dissolves. Potassium permanganate is 
added, and the whole heated to 360-400° F. Finely divided 
waste rubber is added, the mass being stirred and the tem- 
perature maintained. To obtain a harder product sulphur 
may be added. 

Maponite. — A "substitute for India-rubber and Gutta-percha, 
claimed to be capable of use in the manufacture of golf balls, 
tobacco pouches, etc. It is said to be vulcanizable at 260^ F. 
An English patent was applied for by F. E. MacMahon. 

Nigrum Elasticum. — A sulphurized oil substance appar- 
ently made from linseed oil. Very dark colored and quite 
hard. Of English origin. 

Novelty Rubber. — An English substitute invented by David 
Lang. It is made red and drab in color. It comes in small 
slabs about 18 inches square and 2 inches thick, weighing 
about 7 pounds. It is said to be easily mixed with ordinary 
rubber, vulcanized in the usual way, the price being about the 
same as for reclaimed rubber. 

OxoLiN. — An English invention patented by Charles J. Grist, 
an electrical engineer, and identical with "Perchoid" in the 
United States. This gum is used for waterproof sheeting, 
printers' blankets, packings, etc. It is made of a solution of 
partially oxidized oil by adding litharge and heating to over 
400° F. Jute, or other fibers, is then dipped in the oil, the 
surplus oil is removed in a hydro-extractor, and the oil remain- 
ing on the fibers is oxidized by a current of air. These oper- 
ations are repeated twice. The material is then ground with 
sulphur and coloring matters, and treated like India-rubber. 



PARKESINE—PICKE UM. 1 19 

Parkesine. — Made from a compound of linseed oil and 
pyroxyline, and used in the manufacture of small articles that 
are sometimes made of hard rubber. A Parkesine compound 
for molding, proofing, etc., is as follows : To 500 pounds water 
add 50 pounds sulphuric acid, and steep in it as much cotton, 
or rags, or jute, or linen as the liquor will moisten, for 3 or 4 
hours. Take out, drain, and expose the mass to steam heat of 
about 280° F., for an hour, if cotton or jute fiber has been used, 
and 3 hours if flax. Neutralize the acid pulp with a bath of 
water and soda, using 4 pounds of carbonate of soda to every 
200 pounds of rags. Wash and press, pass through a coarse 
sieve of 12 meshes per inch, and dry. Grind the granulated 
material and sift it through a sieve of 120 meshes to the inch. 
The resulting powder may be mixed, in all proportions up to 
equal parts, with fresh rubber. Compounding 25 to 50 parts 
dry Parkesine, with 50 parts alcoholic solvent. A proofing 
compound is : i pound paraffine, linseed oil, or other drying 
oil ; 4 to 8 ounces Parkesine. 

Paragol. — A high grade oil substitute, the basis of which is 
probably corn oil, 

Pensa's Rubber. — A French substitute made as follows: 
100 parts of boiling coal tar, petroleum tar, oil of turpentine, or 
mineral oils, and 25 parts of boric, or phosphoric acid dissolved 
in alcohol, and the vapors are ignited, and the flame extinguished 
as soon as a green color is seen. The mixture is then heated at 
60° C. in the presence of oxygen, until a viscous ductile sub- 
stance is obtained. 

Perchoid. — See Oxolin. 

Peroxide Substitutes. — Peroxide of lead having been rec- 
ommended as a better drier than other oxides used in connec- 
tion with all compounds, the following formulas are given: 
25 parts of walnut oil, 62 parts linseed oil, 5.5 parts peroxide 
of lead, 7.5 parts sulphur. One of the greater toughness is 
composed of 25 parts walnut oil, 56 parts linseed oil, 5 parts 
peroxide of lead, 6 parts sulphur, 6 parts gum juniper. 

PiCKEUM Substitute. — This is made by the following treat- 
ment of Pickeum gum : 



120 SUBSTITUTES FOR RUBBER. 

A 

Boiled linseed oil i6o pounds. 

Vaseline 20 pounds. 

Bastard gum (or Pickeum gum) from Central Amer- 
ica, cut fine 40 pounds. 

Stir and heat to 250° to 300° F., until the gum is dis- 
solved. Then cool to 100° F., and strain. 

B 

{Solution as above 5 gallons. 

Protochloride of sulphur 9 pounds. 

Bisulphide of carbon 9 pounds. 

After the chemical action takes place, the mass is granu- 
lated and the grains are washed and stored for use, or the 
material may be masticated in a rubber mill and run into 
sheets for use. 

PuRCELLiTE. — The invention of Dr. C. Purcell Taylor, of 
England. An insulating substance somewhat similar to Gutta- 
percha, but costing much less. It is said to be very tough and 
elastic, may be made of any color, and is either flexible or 
rigid. The specific gravity of the material is 1.2. It can be 
molded or vulcanized like India-rubber. Its insulation resist- 
ance is equal to that of Gutta-percha. It is unaffected by 
atmosphere, by alkaline or acid liquids, freezing mixtures and 
the like. 

Quinn's Rubber, — ^An English substitute made from petro- 
leum, bisulphide of carbon, chloride of sulphur, and rapeseed 
oil. 

Resinolines. — Substances so called by Eugene Cadoret, of 
Paris, who obtains them by saponifying various oils by the use 
of a metallic carbonate, using by preference carbonate of lead, 
then decomposing by nitric acid, decanting, and saturating 
with an alkali. The soap thus formed is treated with acid to 
form a resinoid body, purified by dissolving in alcohol, and 
evaporating the solution. Resinolines thus formed are very 
similar to natural resins. They are either semi-fluid, pasty, or 
solid. When solid, they are remarkable for their flexibility. 

Rhea Gum. — Rhea fiber washed and dried; immersed in a 
solution of silicate of soda; then carefully dried; then im- 
mersed in a bath of resin or other heavy hydro-carbon oil at 3 
temperature of about 275° F. ; then put in a hydro-extractor 



RICE RUBBER— RUBBERAID. 121 

which is worked at a temperature of 300° F., when the super- 
fluous oil is extracted; the mass is then dried. Later it is 
mixed with gums, resins. India-rubber, or Gutta-percha, and 
Rhea gum is the result. 

Rice Rubber. — Japanese or Machi rice treated so that it 
makes an elastic cellulose product. 

Rosaline. — A vegetable product said to contain about the 
same chemical elements as India-rubber, and of about the 
same specific gravity. Manufactured in the United States, 
France, and England. A strong point is made by the manu- 
facturers that after vulcanization no chemist is able to detect 
that there is anything but pure rubber in a mixture contain- 
ing 25 per cent, of Rosaline and 75 per cent, of India-rubber. 
In vulcanizing, it requires about one-third more time to bring 
about the usual result. 

Ruberine. — An American rubber-like solution used as an 
insulation paint, and also as a proofing mixture, and partaking 
of many of the qualities of ruberoid. It is also manufactured 
in Germany. 

Ruberoid. — An American substitute for India-rubber that 
has the physical appearance of a high grade of black oil sub- 
stitute. In use, however, it differs from many of them, for 
the reason that it has been found useful in vulcanite com- 
pounds, while at the same time it may be used in ordinary 
soft rubber work. 

Rubberite. — An artificial rubber of the same specific gravity 
as fine Para. In color, elasticity, capability for vulcanization, 
and durability, it is said to resemble the higher grades of rub- 
ber. It is the invention of H. C. B. Graves, London, and is 
made up as follows : 

Trinidad asphalt 47 to 80 per cent. 

Oxidized oil 20 to 30 per cent. 

Vaseline 5 per cent. 

Sulphur 15 per cent. 

Chloride of sulphur 3 per cent. 

Rubberaid. — An amber colored substitute manufactured 
from cottonseed oil by a secret process, which removes what 
the inventor calls the grease, leaving an elastic semi-solid 
which has been used quite largely in compounding. 



122 SUBSTITUTES FOR RUBBER. 

Rubber Flux. — A semi-fluid compound of a dark color and 
presumably made from non-drying, non-volatile oils. It is 
used in compounding where the stocks are dry in place of 
palm oil, for example. Is said to prevent oxidation and bloom. 

Russian Substitute. — Manufactured from the skins of rab- 
bits and other small animals, or the v^aste therefrom, digested 
in crude glycerine, and a little water. The formula is 3 parts 
by weight of the cleansed substance melted in water, with 3 
parts by weight of crude glycerine, to which is added \ part 
by weight of a concentrated solution of potassium chromate. 
The resultant mass is flexible. To make it harder, a little less 
glycerine and more chromate of potash are required. To with- 
stand acids, 30 per cent, of gum lac dissolved in alcohol is 
added. For waterproofing fabrics, \ part by weight of oxgall 
is added, with enough salt water to give it the consistency of 
oil. 

Soap Substitutes. — These have been exploited and ex- 
plained more thoroughly by Professor W. Lascelles-Scott 
than by anybody else. The typical formulas that he gives are 
as follows : 28 parts of aluminum soap, 60 parts of linseed oil, 
8 parts of acid free sulphur, 4 parts of oil of turpentine. An- 
other, to use in connection with reclaimed rubber, is 15 parts 
of aluminum soap, 25 parts of devulcanized rubber, 60 parts 
fresh rubber, benzine quantum suMcit. Another still, in which 
a low grade pseudo gutta is used, is 15 parts aluminum soap, 
25 parts Almeidina gum, 5 parts raw rubber, 6 parts sulphur, 
and 4 parts oleum succini. 

SoLicuM. — A substitute or rather a compound patented by 
a chemist in Copenhagen. The basis of the discovery is waste 
rubber and oil. 

SuLo. — A sulphur oil substitute manufactured in the United 
States. 

Textiloid. — A mixture of a resinoline [as described by Cad- 
oret under that heading] with natural resins, cellulose, nitric 
cellulose, or organic substances of animal origin. The result- 
ant material may be transparent, white, or colored. It is 
practically uninflammable, has no smell, is very elastic, and, ii 
submitted to heat, softens, and can be easily drawn out into fine 



TONG OIL—VOLTIT. 125 

threads. It can be used for waterproofing and in various other 
ways is a good substitute for India-rubber. It is flexible and 
elastic. Textiloid is made of 4 parts resinoline, 2 parts nitric 
cellulose, and i part camphor dissolved in alcohol at 90° F. 
The result thus formed may be made in colors by the addition 
of metallic oxides. 

ToNG Oil Substitutes. — Manufactured from the Chinese 
oil known as tong oil, or wood oil. The oil is heated without 
any foreign matter being added to it, at a temperature of 250° 
C, when it becomes solidified. It is then pulverized, and im- 
pregnated with petroleum, which swells it, and renders it 
more easily worked. Patented by Dr. Charles Repin, Paris. 

Turpentine Rubber. — Manufactured by passing spirits of 
turpentine through a heated tube so as to vaporize it, and 
mixing the vapor with hydrochloric or other acid, so as to 
condense and solidify all of the vapor. Patented by A. F. 
St. George, England. 

Tremenol. — A German invention that has reference to the 
production of sulphonic acids, sulphones, oils, resin oils, min- 
eral waxes, etc. Results from a treatment of mineral matter 
with fuming sulphuric acids at ordinary temperatures, or with 
concentrated sulphuric acid at 120° C. The invention further 
calls for the treating similarly of the bodies obtained from the 
oil in their precipitation by means of sulphuric acid. The pro- 
ducts are then washed in brine and water. The inventors 
precipitate glue and gelatine from a slightly acid solution, as 
elastic rubber-like substances that can be drawn into threads 
with perfect ease. 

Velvril. — Basis, a drying or semi-drying oil; treated with 
strong nitric acid. This is compounded with nitro cellulose. 
By varying the proportions any consistency may be obtained 
from that vulcanite to a soft, elastic, rubber-like substance. 
The product is nearly colorless in thin layers, which shows an 
elasticity of about 25 per cent, but no great resilience. Invented 
by W. F. Reid, of England. 

Voltit. — The base of this is glue or gelatine prepared from 
scraps of kid skins, which are treated until they reach a 
gelatinous mass, which is filtered and mixed with oleic acid, 



124 SUBSTITUTES FOR RUBBER. 

such as is used in candle factories, the proportion being 80 
parts of oleic acid to 20 parts of the gelatine. The mixture is 
boiled for -J hour, and then 11 parts of caustic potash solution 
(in 50 parts of water) are added. The boiling is then continued 
for an hour, and a special mass is formed to which are added 
resin oil, oxidized linseed oil, and paraffine. The whole mix- 
ture is then boiled 4 to 5 hours. Also spelled Voltite. It is of 
French origin. 

VoLENiTE. — A substitute for India-rubber and Gutta-percha 
invented by Frederick Lamplough, United States. The com- 
pound is said to be a mixture of resins, or resin oil conveyed 
into a mass of fibrous material by a suitable non-oxidizable oil. 
This latter oil is used simply as a vehicle to carry the resin to 
its place, the process being completed by the distillation of the 
non-oxidizable oil, and the oxidizing of the rest of the mass. 
The oil used is preferably a fish oil, which is refined carefully 
before use. After saturation and treatment the vegetable 
fiber is changed into a homogeneous mass which has many of 
the characteristics of vulcanite. A formula that is said to have 
worked well is 10 parts by weight of fiber, 5 parts resin oil, and 
2 parts fish oil, treated at a temperature of 130° C, for say 4^^ 
hours. 

VoRiTE. — A substitute containing no sulphur and no acid. 
The melting point for the soft grade is from 300° to 400° F., 
and for the harder grade 550° F. It is a floating substitute 
and burns without leaving any ash. It is made in three grades, 
which are distinguished by the names soft, ground, and white. 
According to the makers it absolutely resists oxidation and 
drying out, and is already largely used in the manufacture of 
insulated wire and in general mechanical rubber goods. 

Waterproof Glue. — ^A substitute for canvas proofing made 
as follows : Dissolve 16 ounces of glue in 3 pints of skim milk, 
and to increase its strength add a little powdered lime. 

WiNTHROP Gum. — Another name for Rubberaid. 

Wichmann's Substitute. — A combination of vegetable 
albumen and animal casein. 

Wheat Rubber. — See Cereal Rubber. 

WoLFERT. — A substitute for rubber made of felt impreg- 



ZA CKINGUMMI—HARD R UBBER. 125 

nated with a waterproof substance, presumably vulcanized oil. 
An English invention. 

Zackingummi. — Substitute invented by Zachias Olsson, a 
Swedish chemist. Consists of a mixture of glycerine, chloride of 
calcium, magnesium, and paraffine. 

II. SUBSTITUTES FOR HARD RUBBER AND 
GUTTA-PERCHA. 

Hard Rubber in its best estate is so valuable and perfect a 
product that it would always have the preference were it not 
for its unavoidable high cost. Because of this cost there are 
many substitutes for it that counterfeit it in texture, color, 
and quality, but are never quite its equal in all these points 
of excellence. These substitutes are made of cellulose, gums, 
and animal, vegetable, and earthy matters, having a variety of 
distinctive names and varied uses. To the popular mind, if 
they look like ebonite, they are hard rubber. In the same way, 
Gutta-percha is often confounded with hard rubber, which it 
resembles under many conditions. The following list covers 
not only certain widely-known compounds of hard rubber and 
Gutta-percha, but a number of substitutes for them now put 
to many uses, the chief of which, perhaps, is insulation. 

Alexite. — An American insulating material which can be 
molded in any shape, is waterproof, fireproof, and acid 
proof, and can be produced in any color. In texture and 
general appearance it resembles vulcanite. 

Ambroin. — A German substitute for hard rubber, consisting 
of fiber, silica, and resin compressed to a mass. Its color 
varies from light brown to green or black. Nitric and acetic 
acids do not affect it, and even aqua regia does not injure it. 
Under a moderate heat it softens slightly and can be worked, 
like vulcanite, in a mold. It also takes a bright finish from 
the buffing wheel. 

Armalac. — See Insulac. 

Artificial Whalebone. — A well-known product made as 
follows : India-rubber 20 parts, sulphur 5 parts, shellac 4 
parts, magnesia 4 parts, and gold brimstone 5 parts. Vulcan- 
ized somewhat the same as hard rubber. 



126 SUBSTITUTES FOR RUBBER. 

Bakelite. — A substance said to have the combined proper- 
ties of amber, celluloid, and hard rubber. The invention of Dr. 
L. E. Baekeland. It is a compound of or condensation product 
of formaldehyde and phenol or carbolic acid. It has long been 
known to chemists that formaldehyde and phenol formed con- 
densation products which have been put on the market as arti- 
ficial gums and resins and used tO' some extent. It was further 
known that by a certain process this material was condensed into 
a hard resinous body which resisted every known chemical solvent 
and was only changed by actual burning. This substance was 
usually porous and was of no value. Dr. Baekeland discovered 
that, by carrying on the process in a vulcanizer where heat and 
temperature conditions could be controlled, the reaction could 
be divided into several stages, producing first, a plastic mass 
which can be molded or carved, and on further treatment in the 
vulcanizer where it is submitted with certain chemicals to care- 
fully regulated conditions of heat and pressure, that a hard, 
transparent substance could be produced which is most inert 
chemically. This substance resembles physically and possibly 
chemically the Chinese or Japanese lacquer. It is being manu- 
factured in considerable quantities and seems to have a future, 
but it is in no sense elastic and would take the place of nothing in 
the rubber industry except the hardest of rubber goods. It is 
singularly adapted, however, to manufacture in rubber works as 
most of the machinery can be used with little change. The inven- 
tion is said to be fully protected by patents. 

Balenite, as the name signifies, is intended as a substitute 
for whalebone. It is quite elastic; in other words, it is 
neither hard nor soft, but may be characterized as semi-hard. 
A well-known compound for this is India-rubber lOO parts, 
shellac 20 parts, burned magnesia 20 parts, sulphur 25 parts, 
and orpiment 20 parts. (Hoffer.) 

Betite. — An English insulating material which is said to be 
t)itumen refined to absolute purity and vulcanized. It is used 
on cables, in underground work, for low pressure resistance, 
and in rare instances for high pressure. 

Brooksite. — A compound of resin and heavy resin oils for 
insulating purposes. 



BROWN'S SUBSTITUTE— ELECTROSE. 127 

Brown's Substitute for Hard Rubber. — Made of bitumen, 
sulphur, lead peroxide, and gum camphor. Amalgamated by heat. 

Caoutchouc Aluta. — A composition used as a substitute 
for hard rubber, made of leather scraps boiled in water, with 
a sufficient quantity of oxalic acid to dissolve them, and a 
portion of glue. To this are added resin, pitch, beeswax, and 
copal gum, dissolved in oil. India-rubber boiled in linseed 
oil is then added and a powder formed of plaster of paris, and 
a coloring matter is stirred into the composition to thicken 
and stiffen it. 

Carbo-nite. — ^A cottonseed oil preparation intended as a 
substitute for hard rubber. 

Ce-re-gum. — A compound made by a secret process, and 
which, vulcanized, produces a fairly good imitation of hard 
rubber. Invention of H. W. Morgan, United States. 

Chatterton's Compound. — A widely-known compound 
sold the world over for connections for joint sheets and for 
uniting Gutta-percha parts, and also used for cementing 
Gutta-percha to wood. It softens readily at 100° F., and 
becomes firm again when cold. Its specific gravity is about 
1.02. The best compound is i part by weight of Stockholm 
tar, I part resin, and 3 parts cleansed Gutta-percha, melted 
and mixed. 

Coralite. — A name for vulcanite which is colored to imitate 
coral. 

CoRNiTE. — A specially hard vulcanite or hard rubber, so 
named from the Latin cornu (a horn). 

De Pont Substitutes. — An English patented product made 
from asbestos 30 parts, plaster of paris 5 parts, clay 8 parts, 
copal 15 parts, tar 5 parts, bitumen 15 parts, aniline 2 parts, 
lampblack 15 parts, mica 4 parts, wax 3 parts. 

DiATiTE. — ^A combination of diatomaceous earth, and shellac, 
made under very heavy pressure. It may be made of any 
color, and is used as a substitute for hard rubber. 

Electrose. — A substitute for hard rubber for which the fol- 
lowing advantages are claimed: It will not tarnish metal, as 
no sulphur is used in its vulcanization; it is cheaper than 
hard rubber; it possesses high insulation properties; it can 



128 SUBSTITUTES FOR RUBBER. 

be melted readily into any shape, or made of any color ; it does 
not fade ; it possesses great strength, and takes a high polish ; 
changes of temperature do not afifect it; and it withstands 
the weaker acids and alkalies. 

Ebonitine. — A hard rubber substitute used for phonograph 
records. Is of a brilliant black color. Said to be a good insulator 
and resists acid. Of German origin. 

EsBENiTE. — Made of pure cellulose, chemically incorporated 
with mica in the form of fine powder, with the addition of 
magnesia and a silicate, thus forming strong and close grained 
artificial mica. It is flexible, and can be molded into any 
shape. Esbenite is waterproof, does not burn readily, and is 
thoroughly airproof. Manufactured in England. 

FiBRONE. — A substitute for hard rubber which is a good 
non-conductor, waterproof, and can be handled in a lathe like 
vulcanite. It is said to be durable, does not contract or ex- 
pand, and is made in all colors. It is used for thumbscrews, 
pushbuttons, etc. Plasticon is similar to Fibrone, but heavier 
and of a more stony nature, and probably made of the same 
material. 

Hard Core for Golf Balls. — An English composition 
which consists of lOO parts calcium chloride, 25 parts chloride 
of zinc, 100 parts potato starch. 

Hyaline. — Made of a mixture of equal parts of gun cotton 
and a variety of resins. The gun cotton is dissolved in ether 
and the resins in solution are added, the result being a thick, 
gelatinous mass. When allowed to dry, this mass soon 
hardens and forms a horny, incombustible material. Invented 
by Frederick Eckstein, Vienna. 

Insullac. — A spirit copal resin varnish, with the acids of 
the resins neutralized as much as possible, to prevent the 
resin acids from attacking the copper wire. It is a transparent 
elastic material, and is superior to shellac. Armalac is made 
of black paraffine wax, in solution in petroleum. It remains 
permanently plastic under heat, although it dries quickly and 
thoroughly. Manufactured in the United States. 

Insolacit. — An insulating material produced either as a 
liquid, semi-liquid, or solid. It is not inflammable or affected 



ISO LATIN E— KIEL COMPOUNDS. 129 

by corrosive acids, alkalies, saline substances, etc. It is a 
German product and the compound remains a secret. 

Iron Rubber. — A compound made from iron filings and 
petroleum residue. 

IsoLATiNE. — An American insulating material prepared 
especially for high resistances. It is said to be flexible, not to 
be affected by cold or heat unless the latter is artificial, and 
to be durable. It is also said to protect metal. 

Kempeff Hard Rubber Substitute. — A mixture consist- 
ing of 20 per cent, resin and asphaltum, 15 per cent, china 
clay, II per cent. Kieselguhr. Mixture is allowed to cool; 
ground dry; with 4 per cent, of sulphur, and 50 per cent, of 
ground asbestos fiber. It is elastic and unaffected by acids. 

Keratite. — Another name for hard rubber, derived from the 
Greek word meaning horn. 

Keratol. — An American waterproof preparation, not of the 
nature of rubber, but probably one of the cellulose substitutes. 
It is a colorless transparent substance, and when applied to 
fabrics renders them waterproof and prevents crocking and 
fading. It also strengthens the fabric, and allows stains to be 
washed off. An artificial leather is also made of Keratol. The 
name is adapted from the Greek word keros, meaning hornlike. 

Kiel Compounds. — One of these well-known compositions 
consists of India-rubber, sulphur, pumice stone, oil, and bees- 
wax. The resultant compound makes a hard rubber, said to 
possess a superior elasticity and toughness, and capable of 
being vulcanized in sheets at least 2^ inches thick. This com- 
pound is not affected by the most intense cold, and will stand 
a higher temperature than ordinary rubber. It also burns 
with difficulty. Its ingredients are said to mix faster and 
more uniformly than those of other compounds. It resists 
acids, and other corrosive substances, is a perfect insulating 
material, and is cheap. Another Kiel compound is made of 
India-rubber, sulphur, and mineral oil. The resultant com- 
pound is more flexible than ordinary hard rubber, and when 
warm is more plastic than such compounds. It is also less 
brittle and cheaper, and can be turned in a lathe with greater 
facility and less injury to the tools. 



I30 SUBSTITUTES FOR RUBBER. 

KoRNiTE. — A Russian substitute for hard rubber made at 
Riga. It consists of 25 per cent, of prepared fish bone and 75 
per cent, of scrap horn ground to dust, and then melted 
under high pressure and steam heat. 

Lamina Fiber, — An American invention, used chiefly for 
electrical purposes. It is of various colors, heavier than vul- 
canized rubber, and swells to nearly double its weight when 
placed in water. It is probably a cellulose compound contain- 
ing no rubber. 

Lactitis. — An artificial ivory made from milk, the process 
being coagulation, straining, and rejection of the whey. Ten 
pounds of the curd are then taken and mixed with the solution 
of 3 pounds of borax in 3 quarts of water. The mixture is 
then placed in a vessel over slow fire and left until it separates 
into two parts, one as thin as water, the other resembling 
melted gelatine. The watery part is drawn off, and to the 
residue is added a solution of i pound of mineral salt in 3 
pints of water. (Sugar of lead answers very well as the 
mineral salt.) This brings about another separation of the 
mass, into a liquid and a mushy solid. The liquid is strained 
or filtered off, and at this point coloring matter may be added. 
The solid is now subjected to heavy pressure in molds of any 
shape, and afterwards dried under great heat. The resulting 
product may be used in the manufacture of billiard balls, 
knife handles, or anything for which ebonite or celluloid is 
adapted. 

Leatheroid. — A mixture of American origin, made in black, 
red and gray, and similar to vulcanized fiber. It is insoluble 
in ordinary solvents, uninjured by alcohol, ether, ammonia, 
turpentine, naphtha, or other oils, is very tough, is a good 
insulator, and is of low cost. 

Marloid. — An insulating material said to be made from the 
hides of certain animals, treated by a chemical process, mak- 
ing it so hard that it can be handled in every way the same as 
ebonite. It may be transparent or opaque, and is capable of 
receiving a very high polish. It is said to give an insulation of 
2,000 megohms, is uninflammable, and is of English origin. 



MICANITE—STABILIT. 131 

MiCANiTE. — Mica cemented together under pressure with an 
India-rubber compound. Manufactured in America. 

NiGRiTE. — An insulating compound consisting of a mixture 
of India-rubber and ozocerite. 

Pantasote. — ^A cellulose product made by secret processes, 
largely used in the manufacture of artificial leathers. 

Pegamoid. — This, although covered by several patents, is 
said also to involve certain secret processes. In a general way, 
however, the substance is prepared by treating a fine grade of 
cellulose with a mixture of sulphuric or nitric acid to form 
nitro-cellulose or gun cotton, which is then dissolved in a 
suitable alcohol. The Pegamoid patents call for the addition 
of glycerine, sweet or olive oil, and various coloring matters. 

Plasticon. — See Fibrone. 

Plastite. — ^A vulcanite which is made extra hard and is 
not possessed of any special amount of elasticity. The stock 
recipe for this is : India-rubber 100 parts, sulphur 25 parts, 
magnesia 50 parts, orpiment 50 parts, coal tar asphaltum 60 
parts. It is very hard and solid, and takes a high degree of 
smoothness and polish. (Hof^er.) 

Potato Celluloid. — An Austrian invention relating to an 
artificial solid produced from potatoes boiled 36 hours in a 
fluid containing 8 parts of sulphuric acid and 100 parts of 
water, and then dried. Pipe bowls made from it for the French 
market are said to be hardly distinguishable from real meer- 
schaum. Billiard balls are also said to be made from it. 

Presspahm. — ^An English insulating material made from 
wood fiber so treated that it can be run through rolls into 
sheets of varying thicknesses. It is said to be capable of with- 
standing high temperatures, and is used not only in connection 
with electrical machinery, but also for bookbinding and for 
putting a finish on cloth. 

Sorel's Compound. — A so-called substitute for Gutta-percha 
consisting of 2 parts resin, 2 parts asphaltum, 8 parts resin oil, 
6 parts slaked lime, 3 parts water, 10 parts potter's clay, and 
12 parts Gutta-percha. Five per cent, of stearic acid is some- 
times added. 

Stabilit. — A German invention, the compound for which is 



132 SUBSTITUTES FOR RUBBER. 

a secret, designed to be half way between hard rubber and 
vulcanized fiber. It is not affected by corroding substances, 
and does not absorb moisture. It withstands boiling water 
where hard rubber and vulcanized fiber do not, and is not 
attacked by muriatic acid or sulphuric acid. 

Vegetaline. — Cellulose treated with sulphuric acid, dried 
and ground, then treated with resinate of soda. 

Viscose. — An English cellulose product, used as a substitute 
for vulcanite. It may be of any color or any degree of hard- 
ness. It has been used in connection with rubber, experimen- 
tally, with excellent results. As a friction for belting it is said 
to be excellent, whether or not the belt has the regulation 
rubber cover. 

ViscoiD. — A compound of viscose, formed by mixing with it 
hot bituminous matter such as tar, pitch dissolved in coal tar, 
or the like. The resultant mixture, when solidified, con- 
stitutes a material of a high insulating character, and is pro- 
duced at low cost. The bituminous and cellulose matter may 
be mixed in equal proportions, although there is a wide range 
of compounds that may be made through the use of various 
proportions of the substances. 

ViTRiTE. — A jet black, perfectly hard material, having a 
smooth polished appearance similar to ebonite. It is not 
affected by dampness or acids. It is a good insulator, is of low 
cost, and easily worked. 

VuLCABESTON. — A composition of asbestos and India-rubber, 
forming a product which is a non-conductor of electricity and 
stands the severest tests, resisting heat wonderfully. In- 
vented by R. N. Pratt, United States. 

Vulcanized Fiber. — This material, which is very largely 
used, is made of cotton paper pulp, chemically dissolved, and 
solidified under enormous pressure. It is unattacked by ordi- 
nary solvents such as alcohol, turpentine, ammonia, etc. It 
appears on the market in two forms — hard and flexible. The 
hard fiber resembles horn and is exceedingly tough and strong, 
while the flexible fiber has the appearance of a very close 
grained leather. It is an insulator in dry places, but, as it will 
absorb moisture, it is useless in places requiring waterproof 



MISCELLANEOUS SUBSTITUTES. 133 

qualities. It is made in three colors — black, red, and gray. 
Vulcanized fiber is unaffected by oils or fats, and will stand 
action of hot grease. Low grades have been found adulterated 
with chloride of zinc and calcium, to the extent of nearly 50 
per cent, of its weight. 

WiLLOUGHBY Smith's Gutta-percha. — Gutta-pcrcha re- 
fined by a special process invented by Willoughby Smith. 
Valued in England as giving an increased speed over electrical 
conductors insulated with it. 

Wsay's Compound. — A composition of India-rubber, silica, 
powdered alum, and Gutta-percha. Used in climates too hot for 
Gutta-percha by itself. It is easily attacked by seawater. 

Xelton. — A substitute for hard rubber manufactured prin- 
cipally for use in making battery jars. It originated in Philadel- 
phia. 

III. MISCELLANEOUS SUBSTITUTES AND COMPOUNDS. 

"Apo Elastikon Hyphasma." — An English formula for 
this is : Take caoutchouc and grind it with a portion of residue 
from cottonseed oil. Work in as much vegetable fiber as will 
convert it into a strong felt, adding as much farinaceous matter 
as will fit it for the finishing roller. The outside husk from rice, 
finely ground, is preferable. Stearine pitch may be added to 
give a greater stiffness; also chalk and steatite may be used to 
harden it. 

AsBESTONiT. — An asbestos product manufactured in Eng- 
land under a secret process, for use as steam or hot water packing. 

AsTRiCTUM. — A compound to be used in damp places, con- 
sisting of pulped cotton 15 pounds, pitch 25 pounds, asphalt 20 
pounds, ground granite rock 20 pounds, bitumen 5 pounds, resin 
10 pounds, coal tar 12 pounds, and mastic 5 pounds. 

Caoutchite. — Vulcanized rubber exposed to heat (250° F.) 
for several days and devulcanized and recovered by this means 
alone. 

Cork Leather. — A French invention composed of thin 
sheets of cork, covered on both sides with an extremely thin 
India-rubber skin, and of a textile fabric outside. It is very light, 
is a good insulator against heat, and is waterproof. 



134 SUBSTITUTES FOR RUBBER. 

Belledin's Process for Leather Impregnation. — Hides 
are treated in alkaline solutions and immersed in a bath of rub- 
ber solution. 

Dermatine. — A well known substitute for India-rubber and 
leather, made of an artificial Gutta-percha called "gum percha,*' 
7 pounds; powdered waste rubber, 7 pounds; India-rubber, 14 
pounds; sulphide of antimony, 6 pounds; peroxide of iron, 2 
pounds; flour of sulphur, 4 pounds 8 ounces; alum, 4 pounds 8 
ounces ; asbestos, powder, 2 pounds ; sulphuret of zinc, 3 pounds ; 
carbonate of magnesia, 7 pounds. A little change in this com- 
pound adapts it for machine belts. A variety of colors is gained 
by mixing in various pigments in place of sulphuret of antimony 
or peroxide of iron. The invention is patented by Maxmilian 
Zingler, of London. It is claimed that Dermatine will stand more 
wear than either leather or rubber, that it is absolutely unaffected 
by heat, cold, dryness, or moisture ; and that it will stand perfectly 
the action of grease, oils, or acids. Adaptations of the formula 
given above permit it to be manufactured in molded forms. It is 
used for valves, packing, etc., and also for covering insulated 
wire. 

DuRATE. — An artificial rubber compound said to be similar 
to Dermatine. 

Ekert's High Pressure Compositions. — Consist of rubber, 
asbestos fiber, litharge and sulphur. To this base are added oxide 
of zinc, iron oxide, graphite, magnesium silicate and resin. It is 
patented. 

Endurite. — The invention of John Stuart Campbell, of Eng- 
land. The basis of it is rubber and it is used in golf balls, 
belting, etc. 

Fibrine-Christia Gum is manufactured just as Christia 
gum is, except that silk fibers are used in the place of hemp. 

Frost Rubber. — Another name for what is practically 
sponge rubber made from any ordinary unvulcanized rubber com- 
pound by the addition of a little alum or carbonate of ammonia. 

Gront and Moore's Repair Cement. — A mixture of unvul- 
canized stamp rubber in benzine solution to which are added tur- 
pentine and collodion. 

Harmer's Substitute. — Composed of 150 pounds waste 



HEVEENOID—KIRRAGE. 135 

rubber, 50 pounds Pontianak, 8 pounds African flake, 10 pounds 
Substitute. Patented. 

Heveenoid. — This is claimed to be more insoluble, durable, 
and pliable than almost any other rubber composition. Soft 
Heveenoid consists of India-rubber 32 parts, camphor 32 parts, 
lime I part, and sulphur 8 parts. Hard Heveenoid is made of 
India-rubber 6 parts, camphor 4 parts, glycerine i part, and 
sulphur 16 parts. Heveenoid is the invention of Henry Gemer, of 
New York, and is patented in the United States and Europe. 
Kauri gum is also used in certain Heveenoid compositions. One 
special advantage claimed as to the use of camphor is that the 
chemical compound termed sulphide of camphor is produced, and 
therefore the rubber does not bloom. 

Heveenite. — Another name for Heveenoid. 

India-rubber Leather. — A compound produced by Nelson 
Goodyear in which fibrous substances were mixed with India- 
rubber to form a body the surface of which resembles leather. 

Ireson's Packing Compound consists of a mixture of rub- 
ber, ultramarine blue, and silicate of magnesia. 

Jackson's Compound for Printers' Rolls. — Sixteen 
pounds glue, 16 pounds glycerine, i pound borax, i pound japan. 

Johnstone's Non-Drying Compound consists of Gutta- 
percha, resin and carnauba wax. 

Just's Acid Proof Composition is composed of linseed oil, 
Gutta-percha, sulphur, rosin, shellac, and asphaltum or pitch. 

Kamptulicon. — An India-rubber compound for floor cover- 
ings. The simplest English formula is a vegetable fibrous material 
ground into a coarse powder, mixed with India-rubber, and 
treated with a cheap solvent, such as coal tar or naphtha. Color- 
ing matters are added, if desired. Another Kamptulicon com- 
pound is : Gutta-percha, cheap grade, 6 pounds ; reclaimed rubber, 
12 pounds ; residuum from distilling palm oil, 6 pounds ; ground 
cork, 4 pounds ; ground chalk, 2 pounds ; sulphur, 6 pounds ; hair, 
I pound ; oxide of zinc, i pound. 

Kirrage Compound. — ^A well-known English patented com- 
pound, which takes its name from the inventor. It comes in two 
forms. The first, to be used not over 200° F., is composed of 
India-rubber 12 pounds. Gutta-percha 4 pounds, Stockholm tar 



136 SUBSTITUTES FOR RUBBER. 

25 pounds, chalk 60 pounds, hemp 4 pounds, and sulphur 10 
pounds. The same inventor also recommends the following, to 
withstand a great heat and pressure : India-rubber 20 pounds, tar 
25 pounds, coke, finely powdered, 25 pounds; Stourbridge clay 
25 pounds, sulphur 10 pounds, fine emery 25 pounds, and steel 
filings 5 pounds, 

Leatherine is a compound that closely approaches Derma- 
tine, and in fact a part of the first patent on that product. It 
is intended as a substitute for leather cloth and is made as fol- 
lows : India-rubber 28 pounds, substitute 10 pounds, sulphuret of 
antimony 13 pounds, peroxide of iron 4 pounds, sulphur 3 
pounds, sulphuret of zinc 10 pounds, carbonate of magnesia 23 
pounds, and sulphate baryta 8 pounds. 

Leatherubber Compound. — Made of ground waste rubber 
leather and reclaimed rubber. Manufactured largely in Australia. 

Leonard's Substitute. — Consists of a mixture of corn oil, 
castor oil, chloride of sulphur, naphtha, and oxide of magnesia. 

Luft's Celluloid Rubber. — By boiling equal parts of 
phenol and 50 per cent, formaldehyde with sulphuric acid and to 
the washed and dried product adding India-rubber, a compound is 
formed that boiled in alkaline solutions is transparent and 
similar to celluloid. 

LiMEiTE. — A cement that is manufactured from melted 
India-rubber, with the addition of 8 per cent, of tallow, with 
sufficient slaked lime to give it the consistency of soft paste. The 
addition of 20 per cent, vermilion causes the mass to harden 
immediately. 

Madanite. — A binding material for smooth surfaces, such 
as air-pumps, etc., made of 2 parts by weight of vaseline, and i 
part India-rubber, melted. This mixture may be left for years 
without perceptible alteration. A low grade gum used in the 
same way in connection with vaseline makes an excellent insulat- 
ing tape, and has also been used as a friction gum. 

Metalined Rubber. — A name used for compounds used in 
dental work, under a process patented by C. S. Leadbetter, Man- 
chester, England, for strengthening the gum with a metallic 
fabric, woven or knit. 

Moroccoline. — An imitation leather made from a secret 



OKONITE—THESKELON. 137 

compound which presumably has India-rubber for its base. Made 
in various colors but chiefly as an imitation of Morocco leather. 

Okonite. — A well-known compound for insulating wires 
and cables. According to an English analyst, it consists of India- 
rubber, 49.6 per cent. ; sulphur 5.3 per cent. ; lampblack, 3.2 per 
cent. ; zinc oxide, 15.5 per cent.; litharge, 26.3 per cent. ; and silica, 
0.1 per cent. 

Pantasote. — A secret compound, probably of oxidized oil, 
which is used for the manufacture of artificial leather coverings 
for furniture, bookbindings, etc. 

Pedryoid. — A rubber-like finish for cloth, made presumably 
of oil, in tan, brown, olive, and other colors, and used chiefly in 
shoe finishing. 

Rathite. — A mixture in which waste silk fibers are incor- 
porated with India-rubber to impart resiliency and durability. 
About 6 ounces of silk are used with 28 pounds of rubber com- 
pound. It is employed in making tires, pump valves, packings, 
etc. Patented by A. I. Rath, Cheshire, England. 

RuBBERic, — Fiber blended with India-rubber in solution, 
stretched, and dried. Used chiefly in making rubber tires and 
mechanical rubber goods. Patented by William Golding, Man- 
chester, England. 

Rubber Asphalte. — For road making, a late French patent 
covers a mixture of rubber and asphalt, that after intimate mix- 
ture takes the form of a powder. This is laid hot and under test 
is very cheap and lasting. 

Rubber Velvet. — Manuafctured by sprinkling powdered 
felt of a variety of colors over proofed cloth before vulcanization. 
The result is a velvet-like fabric, elastic and waterproof. 

Theskelon Cement. — A metallic substance used for water- 
proofing and for certain kinds of packings. It will neither ex- 
pand, contract, nor rust. It is used instead of wax for sealing 
purposes, and resists acids, alkalies, and grease. It is often used 
in place of asphaltum. It can be mixed with tar, pitch, asphal- 
tum, and other similar ingredients, the compound possessing ex- 
traordinary adhesive power. Patented by Thomas Smith, London. 

Turnbull's Anti-fouling Rubber Paint. — Pitch and 
resin are melted together, and then a mixture consisting of crude 



138 SUBSTITUTES FOR RUBBER. 

naphtha, dissolved Para rubber, and sifter whiting is added 
thereto. 

Unvulcanized Packing Washers. — Goldstein claims in an 
English patent a washer material for the sheet-metal lids of vessels 
is made, without containing sulphur, of a mixture of crude rub- 
ber, talc, asbestos, and Gutta-percha. 

Voltax. — An American insulating compound not subject to 
chemical change, and proof against water, acids, and alkalies. Is 
cheaper than rubber and does not affect copper — hence tinning of 
the wires is not necessary. 

VuLCANiNA. — A preparation of rubber, a Brazilian inven- 
tion, for paving. 

VuLCANiNE. — A mixture of India-rubber, asbestos, litharge, 
hme, and powdered zinc, to which is added a percentage of sul- 
phur. Mentioned in a patent granted to J. E, Hopkinson, West 
Drayton, England. 

Whaleite. — See Woodite. 

WooDiTE. — A name suggested by Sir E. J. Reed for an India- 
rubber compound invented by Mrs, A. M. Wood. It is said to 
possess the elasticity of India-rubber, to be uninflammable, and 
not injured by salt water. It is used in making valves, packings, 
etc. It is claimed that it will not become sticky or soft under heat 
or steam pressure, and will stand hot grease and other lubricants, 
and neither acids, alkalies, nor wastes from oil refineries, distil- 
leries, etc., affect it in the least. A compound for Woodite or 
Whaleite packing is: Asbestos fiber 38 pounds, asbestos powder 
38 pounds, earth wax 6 pounds, charcoal finely ground 9 pounds, 
ground whalebone 20 pounds. Para rubber 80 pounds, and sul- 
phur 5 pounds. 

Zinsser's Barrel Lining. — A compound for lining casks, 
consisting of deodorized copal, rosin, India-rubber, and a non- 
drying fat, with coloring matter, such as asphalt. 

IV. MINERAL RUBBERS. 

Genasco Hydro-Carbon. — ^A product made from high grade 
asphalt so treated that it is valuable in rubber compounding. 

Kapak. — A product made from treated elaterite. Used in 
general rubber compounding. 



"M R"—INRIG. 139 

LaBelle's Mineral Rubber. — ^A treated elaterite produced 
by an inventor in Utah. 

"M R". — A product of a semi-elastic material similar to 
elaterite which by chemical treatment is made stable and tractable. 
It is wholly neutral, is free from sulphur and acids, and does not 
vaporize under heat. Is largely used in rubber compounding. 

Pioneer Mineral Rubber. — One of the first successful 
asphaltum rubbers used in connection with rubber compounding. 
It unites perfectly with any grade of crude rubber or with re- 
claimed rubber. Is said to prevent blistering, and to minimize the 
harsh action of free sulphur; is acid proof. 

Sarco. — A rubber assistant, probably made from treated 
elaterite. 

Tabbyite. — A mineral product from Utah which seems to be 
a mixture of asphalt and paraffine oils. It is easily manipulated 
and quite elastic. 

V. PUNCTURE FLUIDS AND FILLERS. 

Cyco is a popular compound, said to serve as a preserver of 
tires as well as healer of tire wounds. It is made of vegetable 
gums that will not harden ; neither will it interfere with vul- 
canizing in the event of a large rupture. 

Dow's Inner Tube Filler. — A mixture of paste and 
feathers held in a continuous pocket that covers the tread of the 
inner tube. 

Elastes. — An English compound made of glue, glycerine, 
and chromic salts. 

Everlastic is a substitute for air, and by some considered 
a good compound. As a liquid it is forced into the tire until 
the desired pressure is reached, and in a comparatively short 
time it solidifies and is said to become like rubber. It is not 
affected by heat or cold. 

Fagioli, under a British patent, produces a composition con- 
sisting preferably of these proportions: i pint giant cement, 
i^ pints of rubber solution, and 2^ gallons granulated cork. 

Frankenburg's Puncture Fluid. — Made of dead Borneo, 
oxidizable vegetable oil, and sulphur; a British patent. 

Inrig, under a British patent, prepares a rubber substitute 
from the gelable portions of animals. Fifty parts of such ma- 



140 SUBSTITUTES FOR RUBBER. 

terial are treated with 50 parts of water and from 20 to 60 
parts of oil at a temperature of 200° F. Subsequently sodium 
stannate and potassium bichromate are added. On heating to 
212° F. a mass is obtained which may be set in a mold and 
used for filling motor tires. 

Newmastic. — A tire filler, the component parts of which are 
a secret, but which is apparently of the glue and glycerine type. 

Puncture Closer. — A British compound: 10 parts Gutta- 
percha, 60 virgin wax, 5 tallow, 20 rosin, 5 wild thyme. 

Roland's Puncture Compound. — A glue and glycerine to 
which is added sugar or molasses. 

Rubberine. — A tire filler that is pumped in liquid form into 
the tire and solidifies into a semi-resilient mass. Of English 
origin. 

Scott's Puncture Fluid. — Fifty parts milk, 17 parts isin- 
glass, 200 parts gelatine, 10 parts Carnauba wax, 3 parts formal- 
dehyde, I part gum ammoniacum. Of British origin. 

Suber's Filler. — One ounce Carnauba wax, ^ ounce gum 
tragacanth, ^ ounce water. Add glue and mix in steam. 

Tire Life. — A tire filler of the glue and glycerine kind. 

VI. CELLULOID AND CELLULOSE PRODUCTS. 

Celluloid is made in the main from camphor and nitro- 
cellulose in alcohol, ether being sometimes employed as an 
additional solvent. The paste formed in this way is warmed 
gently, and then rolled out into thin sheets. The product is a 
brittle horny mass, consisting of a chemical, or at least an in- 
timate, mixture of camphor and pyroxyline. A great variety 
of coloring matters may be added to it, and it is susceptible 
to manipulation and processes whereby it has been made quite 
flexible and practically incombustible. Crude celluloid has a 
specific gravity varying between 1.25 and 1.45, and has a 
strong odor of camphor. 

Cellit, — A cellulose acetate. The invention of a German 
chemist, designed to take the place of celluloid, but to be more 
easily worked and safer by varying the organic substance 
that takes the place of camphor. A great variety of products 



CELLULITH—NITRO-CELLULOSE. 141 

is produced. The substance varies from a soft plastic to a 
hard product according to the degree of compound used. 

Cellulith. — A cellulose substitute said to be an improve- 
ment on viscoid. Mixes readily with shellac, rubber, etc. 

Cellulose is a pure substance forming the cellular tissue of 
plants. In the arts use is made generally of cotton or filter 
paper which has been treated with acids to dissolve out im- 
purities, and forms a basis for the manufacture of celluloid, 
gun cotton, pyroxoline, and xylonite. On analysis it shows: 
Carbon 44.44, hydrogen 6.18, oxygen 49.38. It is dissolved in 
sulphuric acid, and is converted into dextrine, and, by prolong- 
ing the action, into glucose. So far it has not been used 
largely in rubber compounding, but both alone and in connec- 
tion with various other ingredients has been applied as a 
waterproofing. It is the basis of certain Swiss puncture fluids. 

Galalith. — A German product from casein. The process 
roughly is to make the casein insoluble by the addition of 
salts and acids. The product is then dephlegmated and dried, 
when, by the addition of formaldehyde Galalith is obtained. The 
process is protected by numerous patents. 

Gun Cotton. — Prepared by treating cotton wool with a 
mixture of strong sulphuric and nitric acids, or nitrate of 
potash may be substituted for nitric acid. After treatment 
with acid the Gun Cotton is rinsed carefully in cold running 
water, and then dried by pressure or by exposure to the air. 
All acid should be removed to prevent danger of explosion. 
Gun Cotton has been used to render fabrics waterproof, for 
varnishing India-rubber to render it impervious to gases, and 
in insulation work. Alexander Parkes, as far back as 1855, 
used a solution of Gun Cotton with gums or resins to take the 
place of compounds of India-rubber. He rendered Gun Cot- 
ton less inflammable by using biphosphate of ammonia, mag- 
nesia, talc, alum, or similar substances. As a good solvent 
for Gun Cotton, he distilled in i gallon of naphtha from 2 to 
6 pounds of chloride of calcium. Charles Macintosh used as 
a solvent equal parts of wood spirit and coal tar naphtha. 

Nitro-Cellulose. — This is produced by the action upon cel- 
lulose of nitric acid or a mixture of nitric and sulphuric acids. 



142 SUBSTITUTES FOR RUBBER. 

According to the length of time the acid is allowed to act, the 
resulting Nitro-Cellulose contains 53.7, 43.6, 36.7, or 28 
per cent, of nitric acid (nitric-anhydride). Gun cotton is 
usually a mixture containing higher percentages while 
Pyroxyline — or, as it is sometimes called, soluble cotton — is a 
mixture of lower compounds. The solution of pyroxyline 
in a mixture of alcohol and ether is called Collodion. 

Pyroxyline. — A species of gun cotton less explosive in its 
qualities, prepared from cellulose by means of nitro-sulphuric 
acid. Its solution in a mixture of ether and alcohol is called 
Collodion. 

Texoderm. — An imitation leather with a hard durable water- 
proof surface. Basis of which is cellulose. 

Weber's Cellulose Compound. — Ten pounds of cellulose 
steeped in a 20 per cent, solution of caustic soda and allowed 
to stand for ten hours; then pressed until its weight is 35 
pounds; then treated with 8 pounds cold carbon bi-sulphide 
for three hours; then emulsified with a mixture of 40 pounds 
Pontianak gum, 15 pounds mineral oil, and 10 pounds stearine 
pitch. 

Xylonite. — See Celluloid. 



CHAPTER VII. 

RECLAIMED RUBBER AND ITS USES. 

Reclaimed rubber, known also as recovered or regenerated 
rubber, shoddy, and crumb, is produced from worn-out rubber 
goods. There are two general methods in vogue, known respec- 
tively as the mechanical and the chemical processes. Where the 
mechanical process is followed, the waste is ground to a fine pow- 
der, which is run over magnets to extract the iron, and is then put 
through a blowing process, which separates the woolen or cotton 
fibers from the rubber. The rubber powder is then subjected to 
a high degree of heat (the process known as devulcanization) , 
and afterwards sheeted, when it is similar to unvulcanized com- 
pounded rubber 

The chemical process is similar to the mechanical, except 
that the fiber is destroyed by means of acid or alkaline solutions 
and quite a percentage of it is washed out with the residue after 
the process is finished. Special grades of reclaimed rubber are 
made from mechanical goods that have high grade frictions in 
them and also from unvulcanized scrap. Rubber is also reclaimed 
from ordinary mechanical goods, such as hose, belting, and pack- 
ing, and for certain purposes is mixed with what is known as 
shoe shoddy. White scrap, from wringer rolls, tubing, druggists' 
sundries, and the like is also produced. The great trouble with 
the white is that, on second vulcanization, it is apt to be very hard. 
At one time, hard rubber dust was to be found in the market and 
was used as a shoddy in certain grades of vulcanite. There is 
to-day but very little of it to be found, however, as most of the 
manufacturers of hard rubber goods find a use for all that they 
make. 

The processes followed in the reclaiming of waste rubber are 
no longer secret. Those who are in the business of manufactur- 
ing for the trade are able to do it as a rule because they buy waste 
stock at a lower figure than a small user could, besides which, by 
manufacturing the goods in large quantities, they can do it more 
economically than it could be done in a small way. In this busi- 

143 



144 RECLAIMED RUBBER. 

ness are used crackers, sheeting mills like ordinary grinders, and, 
indeed, general machinery not dissimilar to that used in a mill 
where crude rubber is compounded. They have in addition, how- 
ever, lead lined tanks for acid treatment, vulcanizers or, better, 
devulcanizers, huge vats for washing, magnets for removing 
metal, sieves, and the like. This branch of the rubber business 
is not supposed to be deeply interested in compounding, in spite 
of the fact that it is sometimes suggested that earthy matters and 
heavy adulterants do find a use in reclaiming mills. 

Rubber scrap of any sort, vulcanized or unvulcanized, is 
eagerly sought for reclaiming, the world over. The larger fac- 
tories use their own scrap of both kinds, yet much unvulcanized 
scrap gets upon the market chiefly in the form of Para cable 
strippings, mackintosh cloth cuttings, frictional fabric, and 
cement ball. 

Next to this in value, and indeed often more valuable is the 
pure gum vulcanized scrap, such as rubber thread, and a variety 
of floating stocks that do not contain rubber substitutes. Special 
high grade stocks such as billiard cushions, balloon fabrics, etc., 
are favorites in this line. 

The greatest single item in scrap collection, is, of course, 
old rubber boots and shoes. They are graded roughly by the 
country of their origin — American, English, German, Russian 
and so on — and their conversion into workable rubber has long 
been the backbone of the reclaiming business. 

Most of the products of the mechanical goods factory come 
into the market as waste eventually, and are sorted and graded 
according to the richness of the compound, and the freedom from 
metal and fabric. In this line is the red scrap such as valves, the 
drab embracing wringer rolls, mattings, buffers, and hose graded 
as air brake, fire hose linings, and garden hose. Then there is 
the grading of belting, asbestos scrap, red and other packing, etc. 

In tires there is the collection and sorting of solid tires into 
cab, baby carriage, omnibus tires. In pneumatics, there are single 
and double tube bicycle tires, motor cycle casing and automobile 
tire shoes — American, French, and German. There is also the 
inner tube in gray, red, and green that is to-day a large factor in 
the recovery business. 



PROCESSES. 145 

In druggists' sundries, water-bottles, and the like furnish 
white rubber. Tobacco pouches, red rubber, while air and water 
beds, sponges and many other specialties furnish regular grades. 

In hard rubber, cells, telephone receivers, sheets and rods are 
ground up and used again, while hard rubber shavings and dust 
find a ready market. 

Gutta-percha in the form of cable strippings, balls, and 
buckets is a type of waste with a recognized place. And these are 
but a few of the many grades put out by the sorters, and sold to 
the scores of reclaiming plants the world over, that turn out the 
two hundred or more millions of pounds of usable rubber from 
what was once thrown away or burned under the factory boilers. 

Almost the first attempt at recovering rubber waste was that 
done at the Beverly Rubber Works, in Massachusetts, back in the 
fifties, when Hiram L. Hall boiled waste vulcanized rubber in 
water, after reducing it to a powder, and then sheeted it. It is 
a curious fact that, in one little mill to-day, the manufacturer 
grinds his own scrap, boils it in hot water until it is in condition 
to sheet, and makes a fair article out of it. 

The year after Hall's patent, another was granted to Francis 
Baschnagel, who paved the way for devulcanization by covering 
a process whereby a finely ground rubber was exposed to the 
action of live steam. It was not, however, until E, H. Clapp 
took hold of the business and discovered a process for blowing 
the fiber out of the finely ground rubber prior to its devulcaniza- 
tion that the goods began to be used to a large extent. 

The next step in the progress of the art was characterized by 
the taking out of a great variety of patents, most of which depend 
upon various acids and alkalies for destroying the fiber. These 
patents were more than fifty in number, and were fully reviewed 
with their attendant processes in the famous suits brought by the 
Chemical Rubber Co. against The Goodyear's Metallic Rubber 
Shoe Co. and the Raymond Rubber Co. While it would be 
tedious to go into that matter, it is interesting to touch upon im- 
portant processes involved. The action of acids upon fibers, of 
course, had long been known ; in connection with the rubber busi- 
ness, however, it was without doubt novel. The Hayward patent, 
for instance, mixed 75 pounds of sulphuric acid with 8 hogs- 



146 RECLAIMED RUBBER. 

heads of water, and in this way the fiber was weakened so thai 
it was easily ground up with the rubber. The Faure patent called 
simply for the immersion of the clippings in an acid, which in 
disintegrating the textile matter set the India-rubber free. Hiram 
Hall advised the use of lime or alum to eat up the cloth, and also 
a solution of i part of sulphuric acid to 9 parts of water. Burg- 
hardt used muriatic acid for destroying the cloth fiber. The 
Heinzerling patent called for a treatment first with acids, and 
then with alkalies. It is also to be remembered that Charles 
Goodyear directed that crude India-rubber should be subjected 
to a 10 per cent, solution of sulphuric acid to eat up the bark with 
which the gum might be contaminated. 

The Mitchell patents, the Bourn patents, and others, where 
an extremely dilute acid was used, and where a concentrated 
acid was called for, have been so thoroughly reviewed that those 
familiar with the rubber business know all about the processes 
employed. 

What is known as the alkali process, based upon the patents 
of Arthur Hudson Marks, is one of the notable discoveries in 
reclaimed rubber in more recent years. Factories for reclaiming 
under this process are operated in the United States, England, 
Germany and Belgium, mechanical waste being chiefly used. 

In addition to the processes in more general use, a few 
unusual ones may be interesting. For example, the Tors- 
trick process, in which dilute nitric acid and fusel oil were mixed 
with the gum in a heated state, or passed through it in the shape 
of vapors, making the mass sticky, after which a small quantity 
of chloride of calcium was added and the gum sheeted. 

Conrad Poppenhusen mixed rubber scrap with essential oils, 
a little turpentine being used preferably, left the scrap until it had 
become soft, and then passed dry gaseous ammonia into the mass, 
forming a gelatinous viscid product. 

C. F. E. Simond mixed 2 parts of chloride of lime with 100 
parts of waste rubber, and brought it to a high degree of heat, 
by which the sulphur was volatilized, which took from 15 to 60 
minutes, and then used the rubber over. 

Thomas J. Mayall mixed vegetable tar with waste rubber — 
exposed it to the heat of the sun, or to a gentle artificial heat, and 



PROCESSES. 147 

got a soft pasty mass that he was able to work with crude rubber. 
He also invented a process for sprinkling the finely ground rub- 
ber with camphene and setting the mass afire in a partially covered 
vessel, his claim being that if the fire was stopped at a certain 
point, a tough viscid mass was the result, which contained neither 
sulphur nor fiber, and could be reworked like unvulcanized rubber. 

Beylikgy exposed vulcanized rubber for a number of days to 
a temperature of 250° F., after which he claimed that it became 
an adhesive mass, insoluble in alcohol, partially soluble in 
ether, and wholly soluble in benzole. He called this caout- 
choucite and claimed that it could be vulcanized with the addition 
of sulphur at a lower temperature than ordinary crude rubber. 

McCartney, of Glasgow, mixed vulcanized rubber with 
naphtha and a little acetic acid. He also added camphor, and by 
the action of heat produced in reality a rubber paint. 

The following are briefs of some of the later claims of 
inventors in rubber vulcanizing : 

Anderson's process (English). Ground scrap is mixed with 
calcium sulphide and coal tar naphtha, exposed to heat, and 
thoroughly washed. 

Alexander's process relates to the production of India-rubber 
latex from rubber waste. The waste is heated under pressure in 
benzine. The dissolved matter is then removed, and the solution 
is heated again in sodium hydrate. The benzine is distilled off 
and the aqueous solution of caoutchouc filtered and precipitated 
with acid. 

Basle process. A Swiss process which covers the use of 
various ethers boiling at a temperature of about 100° C. 

Brimmer's process (German) consists of mixing ground 
scrap with Ricinus oil, heating until dissolved, adding alcohol for 
precipitation and washing with a weak solution of caustic soda. 

Clift's process (English). Waste rubber is dissolved in a 
base of the pyridin group, then treated with acid in the presence 
of a volatile solvent for the separation of the rubber from the 
base then separating the solvent with the rubber in solution. 

Chautard process (French) uses commercial phenol for re- 
claiming, the phenol being later distilled off. The whole process 
is quite intricate. 



148 RECLAIMED RUBBER. 

Durvez process (Belgian). Rubber waste boiled with water 
and finely powdered lime. Product is washed, rolled, and dried. 

Eves's process (American). Devulcanizing by treating with 
sodium sulfate in the presence of heat, then incorporating barium 
chloride. 

French process. Waste vulcanized rubber is heated with 
terpin hydrate, the mixture is then treated with boiling water, and 
from the residue the regenerated caoutchouc is extracted by 
means of a suitable solvent such as commercial xylol. The terpin 
hydrate is recovered for use over again by cooling the hot aqueous 
wash-liquors. 

French process. The finely divided rubber is heated, pre- 
ferably at iio° to i8o ° C, under pressure, with a soap solution, 
to which may be added other substances such as aliphatic or 
aromatic hydrocarbons, oil of turpentine or the like, and salts 
capable of forming solutions which dissolve sulphur, such as 
alkali sulphides, alkali sulphites, etc. 

Gilbert-Besaw process (American). This process is not 
patented, but is secret. It is applicable to the recovery of any sort 
of rubber scrap, whether cured in open steam, in molds, or in 
dry heat. According to the statement of the inventors, no acid 
or alkali, or anything that can be in any way injurious, is added. 
The machinery for treating the waste rubber for the removal of 
fiber and for devulcanization is individual to the process. The 
time occupied in devulcanization is about one-quarter that used 
in existing processes. No residuum or oily matter of any sort 
is added to the product, either before or after devulcanization. 
The results of this process for insulation purposes, in reducing the 
acetone test, is of itself invaluable. 

Gregory and Thom's process (English). Reclaimed in the 
usual way; then add a solvent which is a mixture of aniline oil 
and naphtha. The product is heated in open steam until the solu- 
tion of rubber is complete, when it is taken out and strained. 

Gubbin's process (English). Unvulcanized scrap in which 
the fabric is saturated with naphtha and passed through plain 
pressure rolls to remove the rubber from the fabric. 

Heinzerling's process (German). Ground waste rubber 
treated with aniline or their homologues at 140° to 180° C. The 



PROCESSES. 149 

rubber is then mechanically separated from the residue ; is treated 
with dilute sulphuric acid, and the separating rubber is washed 
and dried. 

Heyl-Dia's process. Heats ground rubber under moderate 
pressure in naphtha, temperature being not more than 120° F. 
The naphtha is then drawn off and with it most of the sulphur. 
The rubber is then heated to over 350° F. with a fresh solvent 
when it dissolves. The solvent is then removed and the sulphur 
washed and dried. 

Hyatt and Penn's process. Waste rubber finely ground is put 
into a vacuum chamber and molded into goods under heat. 

Karavodine's process (French) consists of pulverizing the 
material, adding asbestos fibers which have been previously 
treated with a binding medium, and subjecting the mass to a 
higher pressure at higher temperature. 

Kessler's process. Waste rubber is treated with carbolic 
acid in a vacuum. After solution powdered acetate of lead is 
added and the whole submitted to distillation. Caustic soda is 
used later for neutralizing. 

Kittel's compound (Austrian). Powdered waste mixed with 
caustic alkalies is compressed into cakes and heated 2 or 3 hours 
at 280° C. 

Koneman's process (American). Ground waste is boiled 
in a salted-acid solution, and a mixable fixed hydrocarbon is then 
added. 

Koener's process (German), Waste rubber is heated with 
solvents such as benzine for a time, after which the solution is 
further heated with water and the solvent subsequently distilled 
off. 

Marks's process (American). Waste rubber finely ground is 
heated in a dilute alkaline solution in a closed vessel for a time 
and at a temperature dependent upon the amount of sulphur 
present. 

Murphy's process (American) uses for devulcanizing, a 
bath consisting of carbonate of soda and gallic acid, 

Neilson's process (German). The inventor uses resin oil 
as a solvent, filters and precipitates the rubber by means of a 
ketone. 



150 RECLAIMED RUBBER. 

Passmore's process dissolves vulcanized waste with eucalyptol 
and removes mineral matters by filtrating. The eucalyptol is 
driven off by having steam forced through the mass. 

Penther's process (German). A devulcanizing machine of 
German origin makes what is known as American reclaimed rub- 
ber. It separates the fiber from the rubber so thoroughly that 
the fluff is a merchantable product in the felt trade. 

Peterson's process (American) consists in subjecting 
shredded waste to an alkaline solution raised to a boiling tempera- 
ture under hydraulic pressure, next washing in water solution 
containing phenol under a high temperature and pressure. 

Price's process (American) uses caustic solutions of marked 
strength, under ordinary atmospheric pressure. 

Price's process (English). A process whereby waste rubber 
cut into pieces of suitable size is roughly mixed with crude rubber 
and ground flint, and without being vulcanized, by great pressure 
molded into finished goods. 

Roux process (French). The inventor describes a machine 
which devulcanizes powdered waste rubber and makes it into 
tubing at the same time. In other words it is a combination of a 
devulcanizer and tubing machine. 

Steenstrup's process. The waste is heated in a solution of 
alkali and hydrofluoric acid under steam. The product is then 
washed, dried, etc. 

Theilgaard's process (Denmark). The inventor has several 
patents which cover the treatment of vulcanized scrap by alka- 
line earths and such solvents as sodium sulphide. 

Wheeler's process (American) consists in subjecting the 
waste particles individually to a current of heated fluid moving 
through a confined passage. 

Zuhl's process (English). Vulcanized waste is dissolved in 
five times its weight of naphthalene at a low temperature. The 
naphthalent is then distilled from the mixture with same. 



CHAPTER Vlil. 

RESINS, BALSAMS, GUMS, EARTH WAXES, AND GUM-LIKE SUBSTANCES 
USED IN RUBBER COMPOUNDING. 

A GREAT variety of vegetable, mineral, and animal resins and 
waxes find uses in admixture with India-rubber and Gutta- 
percha. Their important uses are to render compounds 
adhesive, as in frictions, to assist in insulation, to add luster, 
and to modify the texture of the vulcanized compound. Many 
gums, like many earths, lend special virtues which they 
possess to rubber compounds. The more important of these 
materials, and those most generally used, are described in the 
following pages. 

Adamanta Resin. — An imitation copal, manufactured from 
common resin by a special hardening process. It is not 
soluble in alcohol or benzine, but completely so in boiling 
turpentine. It is free from acids and alkalies, and has the 
same melting point as Zanzibar copal. It is used rarely in 
rubber shoe varnish, and often in cheap frictions in mechan- 
ical lines, being moistened with resin oil to increase its 
adhesiveness. 

Amber. — A fossil resin chiefly found in Prussia, on the 
shores of the Baltic sea; it occurs also in Sicily and some- 
times in the United States. It is the hardest and heaviest of 
the resins. Its specific gravity is about 1.07. By distillation 
a yellow oil — oleum succini or oil of amber — is obtained, and 
a yellow resin remains in the still. Amber varies in color from 
light yellow to a deep brownish red. It is insoluble in almost 
all of the ordinary solvents. When heated above its melting 
point, however, it becomes partly decomposed, and is then 
soluble in oil of turpentine and alcohol. It makes a very fine 
transparent varnish, which is used on negatives in photo- 
graphing. It is used in cements for fastening linoleum and 
rubber tiling to decks, and is also mentioned in the formulas 
for certain patented gums. 

Asphalt is undoubtedly an oxidized residue from evapor- 

151 



152 GUMS AND BALSAMS. 

ated petroleum. This name is applied usually to the solid 
bitumen, the liquid being called mineral tar, and sometimes 
maltha. It is chiefly made up of hydrocarbons, but contains 
a certain amount of sulphur and nitrogenous bodies. It is 
known also as natural pitch, Jews' pitch, asphaltum, bitumen, 
etc. It is a black hard substance which, when freshly broken, 
shows shining surfaces that are always correspondingly round- 
ing and hollowing. It is insoluble in water and alcohol, but 
dissolves in benzine, acetone, and carbon disulphide. Is used 
in rubber compounding in place of coal tar, and in insulating 
compositions, and in certain substitutes like Kerite. Com- 
mercially there are two grades, known as "lake pitch" and 
"land pitch," of which the latter is the harder. 

In solution it is used sometimes to protect rubber goods 
that are exposed to the destructive influence of brine. A 
little Asphalt is also said to increase the elasticity of hard 
rubber. Asphalt mixed with resin and oil of tar forms a low 
grade artificial Gutta-percha. It is added to "Cooley's arti- 
ficial leather" to harden it and enable it to resist heat. It is 
also the basis of one type of marine glue. 

Artificial Asphalt. — This is made by heating sulphur and 
resin together to about 250° C, where the reaction takes 
place, attended by the evolution of sulphuret and hydrogen, 
and leaving an almost black, pitchy substance resembling 
asphalt. It is insoluble in alcohol, but dissolves readily in 
benzine. 

AuvERGNE Bitumen. — A species of natural asphalt found in 
the province of Auvergne, France. It is similar to Trinidad 
asphalt, but is impure, containing clay, silica, magnesia, iron, 
and traces of arsenic. (See Asphalt.) 

Balsam. — This term is given to oleo resins which are soft at 
ordinary temperatures, and are really a mixture of such a 
resin and the essential oil of the plant from which they 
exude, such as benzoin, tolu, etc. 

Balsam of Storax. — Produced from the inner bark of a 
tree of the genus Storax, in Asia Minor. Commercially it is 
a soft, coarse, dark colored powder, or, more commonly, a 
semi-fluid, adhesive substance, brown outside, greenish gray 



BALSAM OF SULPHUR— BITUMEN. 153 

inside. The sweet gum of the southern United States is 
alHed to the Eastern drug, and was formerly much used in 
chewing gum. Used in general cements, being particularly- 
good in leather cements; also for glass, stone, and earthen- 
ware cements. 

Balsam of Sulphur. — A solution of sulphur in boiling 
volatile or olive oil. Used in certain rubber compounds as a 
vulcanizing agent and a protection against blooming. 

Beeswax is obtained from the comb built by honey bees. 
The crude wax is yellow and soft, with a granular fracture. 
Its specific gravity varies between .965 and .969, its melting 
point being between 140° and 144° F. It is often adulterated 
by water, by white mineral powders, and by cheaper sub- 
stances, such as vegetable wax, paraffine, etc. White wax is 
that which has been exposed to the sun or to the moderate 
action of nitric or chromic acid, thereby being bleached. It is 
sometimes used with rubber in medicinal plasters. Ordinary 
beeswax is largely used in Kiel's hard rubber compounds. 
Sheet beeswax is often used in the work of vulcanite pattern 
making. It is also used in processes for making fabrics water- 
repellent, the other ingredients being aluminum, resin, soap, 
wax, and silicate of soda. With Gutta-percha it is an in- 
gredient in shoemakers' wax, and also in certain proofing com- 
pounds. Hancock used it in a Gutta-percha compound for a 
soft effect. In a hard rubber compound made up of India- 
rubber, sulphur, oil, and pumice stone, it is said to be acid 
proof. 

Birch-bark Tar. — A peculiar tar obtained during the dis- 
tillation of birch-bark for oil, being probably the same as 
Russian Jackten extract. Used in the manufacture of certain 
rubber substitutes. 

Bitumen. — The term applied to a body made up of several 
hydrocarbons. It resembles Trinidad asphalt and is of the 
same nature. Its specific gravity is from 1.073 to 1.160. Arti- 
ficially it is prepared from shales, mineral asphalt, etc. It is 
used as a source of paraffine. The West Indian product is 
known as Chapapote. A solution is made from it in which 
the tapes are soaked that are used for covering wire that has 



154 GUMS AND BALSAMS. 

been insulated with India-rubber. Bitumen has been utilized 
by what is known as the calender process, which is a partial 
vulcanization, rendering it valuable as an insulator. 

Black Pitch. — Is the residue left after the oils of tar have 
been distilled from that body. Used in weather proofing 
work. 

British Gum. — See Dextrine. 

Burgundy Pitch. — Is obtained from the hardened juice or 
sap which concretes upon the bark of the Norway spruce. As 
imported it is often quite impure and should be melted and 
strained before being used. It is almost entirely soluble in glacial 
acetic acid or boiling alcohol, and somewhat in cold alcohol. 
When pure it is hard and brittle, with a shining fracture, 
dissolves in benzine, acetone, and carbon disulphide. Is used 
reddish or yellowish-brown, aromatic. It is much used in 
cements, in electric tape, and in the manufacture of porous 
plasters. Common resin is often melted and mixed with fats 
and water, forming a gum that much resembles Burgundy 
Pitch. 

BuRMiTE Amber. — Found in Burma, but quite inferior in 
quality. It is a little harder than amber proper, is easily cut, 
takes an excellent polish, but has less variety of color. (See 
Amber.) 

Button Lac. — See Shellac. 

Canada Balsam. — Sometimes called Canada Turpentine. It 
is derived from the Ahies halsamea. It is a yellowish or greenish 
transparent liquid, completely soluble in ether, chloroform, or 
benzol. It is sometimes called Balsam of Fir, but it does not 
really belong to the balsams, being a true turpentine. Stras- 
burg turpentine is sometimes substituted for it commercially. 
It is used in certain compounds to prevent sulphur from 
efflorescing. With paraffine, beeswax, and coloring matters, 
it is used for insulating colored yarns that are used for anun- 
ciator and similar wires, and it was also used by Dtincan in 
Gutta-percha cements for leather. 

Candle Tar. — The residual products from the distillation of 
animal fats, oils, etc., are known as candle tar. This product is 
sometimes soft and ropy, and at other times quite hard. 



CASEIN— CHERRY GUM. 155 

Mixed with sulphur, it is said to produce a compound having 
some of the elasticity and other desirable qualities of vulcan- 
ized India-rubber. 

Casein (also called Caseum) is one of the chief constituents 
of milk, being that part which forms the curd of sour milk, 
and is familiar in the form of cheese. A similar substance, 
prepared from peas, beans, lentils, and the like, is called 
vegetable Casein. It is used in shower-proofing after a Ger- 
man formula in connection with soda, lime, and acetate of 
alumina; also, in cements of which Gutta-percha is the base, 
for joining small particles of leather, shavings, etc. In Kittel's 
compound Casein dried and powdered is mixed with linseed 
oil. India-rubber or Gutta-percha is then added to the com- 
pound. A sample compound is India-rubber 10 parts, Casein 
20, superoxide of lead 10, sulphur 3, and linseed oil i. 

Carnauba Wax is found in Brazil, where it forms as a 
coating on the leaves of a certain palm (Corypha cerifera), and is 
removed by pounding and shaking. It is very hard and is of a 
greenish or grayish color. Its specific gravity is about 0.995, 
it is odorless, and melts at 185° F. It dissolves completely in 
boiling alcohol, and is used on insulated wire as a finish, and 
in the manufacture of wax varnishes. 

Carn Gum. — Used instead of ozocerite as a finish for tape 
or braids that cover insulated wire. (See Carnauba Wax.) 

Ceramyl. — A material used in the finishing process in the 
manufacture of elastic web. Its use is to make the web 
stronger, and in a measure to act as a size, causing it to lie 
flat. It is also said to add strength to it. By the application 
of heat, ceramyl, which comes in the form of a semi-solid, is 
reduced to a liquid. In English practice this is said to have 
driven out the use of glue in the dressing of elastic webs. 
Ceramyl is manufactured in England. 

Cerasin, also spelled Ceresine, is of a butter yellow color, 
odorless, and has a specific gravity of .918 to .922. It is used 
chiefly in covering annunciator wires where the object it to pre- 
serve the colors of the yarns in the braiding. (See Ozocerite.) 

Cherry Gum. — A pale yellow or red brown gum, coming 
from the bark of old cherry trees. It contains 35 per cent, of 



156 GUMS AND BALSAMS. 

cerasine, 52 parts of arabicum, and i to 3 per cent, of ash. This 
gum is chiefly used in the manufacture and finishing of fine felt 
hats. The gums on the market are of two quaUties, the German, 
which is the best, and the ItaHan. It is used in insulating instead 
of purified ozocerite, in certain cases where a little more adhesive- 
ness is required. 

Coalite Pitch. — A residue of Coalite tar, much like natural 
bitumen and containing little free carbon. An English product. 

Coal Tar. — See Tar. 

CoLOPHANE. — See Rosin. 

Colophony. — See Rosin. 

CooRONGiTE. — ^The name given to a rubber-like mass found in 
Coorong, South Australia. Some place it among the fossil resins. 
Coorongite is not soluble in the ordinary solvents used in rubber 
work, but, after mixing with India-rubber, it can be put in solu- 
tion. According to Forster, it vulcanizes somewhat as India- 
rubber does. (See Psuedo Rubbers.) 

Dextrine is a sort of intermediate product between dextrose 
and starch. It is soluble in cold water, and is much used as .1 
substitute for gum arabic in mucilage, as it. has strong adhesive 
properties. Cooley combined it with a little Gutta-percha, resin 
oil, and earthy matters in the production of what he called arti- 
ficial leather. It is used also in a mixture with plaster of paris, 
making a tough surface mold for small experimental rubber work. 

Dextrose is obtained from starch generally, and is crystal- 
lized glucose. It is soluble in water, and has many commercial 
uses. For example, it was used by Hancock as a sizing for cloth 
on "which was spread rubber in solution, the Dextrose being there 
in order to keep the rubber from sticking to the cloth. In other 
words, this was a sort of cheap calendering process. 

Earth Wax. — See Mineral Wax. 

Elaterite is also known as elastic bitumen or mineral caout- 
chouc. It appears naturally in soft, flexible masses of a brownish 
black color somewhat resembling India-rubber. It is composed 
of 85.5 per cent, of carbon, and 13.3 per cent, of hydrogen. In its 
physical characteristics, Elaterite is found in infinite variety. It 
is sometimes elastic and so soft as to adhere to the fingers, and 
sometimes brittle and hard. One kind of it, when fresh cut, re- 



ELASTIC GLUE— GLUCOSE. 157 

sembles fine cork, both in texture and color, and will rub out 
pencil marks. Its elasticity is due to its cellular texture, and to 
the moisture with which it combines. It is used to a certain extent 
in insulating compounds, but is intractable and so far shows no 
special features of value above other minerals of the same series. 
A few years ago a company was formed in Colorado which 
claimed to be able to make many kinds of rubber goods from this 
product alone, but little has been heard of the plan of late. (See 
Gilsonite.) 

Elastic Glue is used with India-rubber and Gutta-percha 
in shoemakers' cements. (See Substitutes.) 

French Asphalte. — See Auvergne Bitumen. 

FiCHTELiT. — Occurs in a peat bed near Redmitz in the Fich- 
telgebirge in Germany, and also in fossil pines in the form of 
scales or flat needles. It has also been met with in Franzenbad 
and in Denmark. A hydrocarbon little known, though mentioned 
in certain patented rubber compounds. 

Fish Glue. — Made by boiling the heads, fins, and tails of 
fish by high heat. It is generally made into a liquid glue by a 
treatment with acetic or hydrochloric acid, whereby its property 
of gelatinizing is lost. It would have a disagreeable odor were 
it not for the fact that that is destroyed by adding cerosite or oil 
of sassafras or something of that kind. Fish Glue is used in a 
cement for cured rubber, in connection with Gutta-percha and 
rubber dissolved in bisulphide of carbon. (See Glue.) 

Garnet Lac. — See Shellac. 

Gilsonite. — A hydrocarbon valued for its elasticity. One 
of the purest of crude bitumens, it is mined in the Uncompahgre 
Indian reservation, Utah, United States. It is a black, tarry-look- 
ing substance of brilliant luster. It is used for varnish making, in 
paints, and for insulation, either with or without rubber, one well- 
known compound consisting of rubber, linseed oil, and Gilsonite. 

Glucose. — The commercial form is prepared from starch 
usually, as that is the cheapest raw material. The starch paste 
being boiled with mineral acids, dextrose, maltose, and dextrine 
are produced. Glucose in this country is made entirely of corn- 
starch; in Europe, however, sago starch, rice, and potato starch 
are used. It is neutral, and both odorless and colorless. It is 



158 GUMS AND BALSAMS. 

really a kind of sugar that is with difficulty crystallizable, and it 
is also called grape sugar. It occurs in commerce either as a thick, 
sweet, heavy liquid, or as a white solid mass. It is used with rub- 
ber, glue, sugar, whiting, and glycerine in making bookbinders' 
cements, and in making puncture fluids for pneumatic tires. 

Glue. — ^An impure form of gelatine obtained from the horns 
hoofs, skins, and bones of animals. Glue of good quality should 
be bright brown or brown yellow in color, free from specks, 
glossy, perfectly clear, hard, and brittle, should not become damp 
by exposure to the air, and should snap or break sharply when 
being bent, the fracture showing a glassy, shining appearance. 
Used in bookbinders' cements, in cheap frictions, and in cheap 
horse-cover compounds with rubber. A size made of glue was 
used by Brockedon to protect fabrics that come in contact with 
the liquid used in cold curing. This was afterwards dissolved off 
by an alkaline solution. 

Glugloss Gelatine. — A gelatinous product used largely in 
America in waterproofing fabrics. It is dissolved in hot water to 
use, and makes an excellent waterproof sizing. A mixture of 
glycerine with it increases its elasticity. It combines readily with 
glue, dextrine, or any such products, and develops considerable 
adhesiveness. 

Gluten. — A vegetable substance obtained from wheat and 
other grains. Treated with tannic acid, it is used as a substitute 
for Gutta-percha under a formula by Johnson, who says the pro- 
duct can be vulcanized. Another formula calls for its mixture 
with oil and sulphur, as a substitute for Gutta-percha. In cements 
it is the basis of one for uniting leather scraps, and is used with a 
little Gutta-percha. 

Gum Anime is a South American fossil resin similar to 
copal. It occurs in small irregular pieces of a pale yellow color. 
Has a high melting point, and its specific gravity is 1.028 to 1.072. 
Mixed with rubber and earthy matters and dissolved in turpen- 
tine, it formed one of the early compounds for clothing. 

Gum Arabic is an exudation from a species of Acacia. It 
is made up of clear or semi-transparent fragments, hard and 
brittle, breaking with shining fracture. It is inodorous and feebly 
sweetish to the taste. Its specific gravity is 1.3 1 to 1.52, for dried 



GUM AMMONIACUM— CAMPHOR. 159 

gum. It comes from Africa and is known also as Acacia and 
Gum Senegal. It dissolves in hot or cold water. It is used in 
connection with plaster of paris in making a tougher surface 
mold for small and experimental rubber work. Enough gum is 
added to make the mixing solution about the thickness of a thin 
syrup. It is largely used in cements. It is also used in certain 
shower-proof compounds, and in paste blackings made of caout- 
chouc oil, vinegar, molasses, and boneblack. 

Gum Ammoniacum. — Exclusively obtained from Persia as 
tears, or aggregated masses, of a peculiar smell and a taste 
slightly sweetish, bitter, and somewhat acrid. Its specific gravity 
is 1.207. Used in solutions for pressed leather cuttings and 
fibrous wastes. Ten parts of this gum mixed with 20 or 25 parts 
of Gutta-percha form a cement possessing both elasticity and 
solidity, and is thoroughly waterproof, used for filling cracks 
in horses' hoofs. Also used with Gutta-percha, boiled linseed oil, 
and dry casein or caseum, for sticking together small particles of 
any dry matter in the production of artificial leather. 

Gum Benzoin. — Occurs in lumps of yellowish brown tears, 
stuck together and more or less mottled from the white inside the 
tears. Its specific gravity is from 1.063 to 1.092. Of an agree- 
able balsamic odor and very little taste, but irritating when 
chewed for some time. Used in linseed oil proofings, presumably 
to kill odor; also in certain Gutta-percha and India-rubber com- 
pounds for disguising the odors. Four per cent, of the weight of 
the mass is said to be sufficient to make the odor an agreeable 
one. According to Forster, a little of it mixed with Gutta-percha 
greatly improves the quality. 

Gum Asphaltum. — Refined natural bitumen, also called 
litho-carbon. Is found in Texas and at one time was exploited as 
a substitute for rubber. (See Litho-Carbon.) 

Gum Camphor. — The white transparent substance known by 
this name is obtained from Japan and the island of Formosa. It 
is really an oxygenated essential oil. Its specific gravity is 0.985. 
Sparingly soluble in water, and very soluble in alcohol, ether, 
acetic acid, and hydrocarbons or volatile oils. Is largely used in 
the manufacture of celluloid. Gum Camphor is also used in 



i6o GUMS AND BALSAMS. 

compounds of the substitute order like Textiloid, Kerite, etc. 
Was also the basis of the Heevenoid compounds (which see). 

Gum Copal. — Hard Copal is a fossil resin obtained from the 
East Indies, South America, and the eastern and western coasts 
of Africa, It occurs commercially in roundish, irregular pieces, 
having a specific gravity of 1.045 to 1.139. It is insoluble in 
alcohol, partially soluble in ether, and slightly so in oil of tur- 
pentine. Soft Copal is obtained from living trees in New Zealand, 
the Philippine Islands, Java, and Sumatra. Used with shellac, 
asphaltum, and arsenate of potash for waterproofing leather ; also 
in cements, in proofing compounds, and in varnishes in connec- 
tion with India-rubber, lead, alum, and other ingredients dissolved 
in spirits of turpentine. 

Gum Dammar is derived from the Amboyna pine, growing 
in the Malay peninsula, Sumatra, and Borneo. The resin exudes 
in tears and is collected after it has dried. It makes a very trans- 
parent varnish, the gum being soluble in benzine, essential oils, 
and to a certain extent in alcohol. Used in artificial leather com- 
pounds, and with rubber, asphalt, and fish oil for waterproofing 
leather. It is quite largely used in rubber cements. 

Gum Elemi comes from the Philippine Islands, and is a 
rosin obtained from certain trees there. It varies from white to 
gray in color, and is quite soft and very tough. Alcohol and 
other solvents readily dissolve it, and its office usually is to give 
toughness to varnishes in which are harder resins. Used in con- 
nection with India-rubber and benzine in the production of 
puncture fluids. (See Manila Gum.) 

Gum Euphorbium appears in the market in the shape of 
tears of irregular shape, varying in size from a small pea to i|- 
inches in length. Of a dirty gray or yellowish color, and very 
largely mixed with impurities. Must not be confused with Gum 
Euphorbia (which see). 

Gum Frankincense, — ^Also called Olibanum (which see). 

Gum Gamboge. — The best is found in commerce in cylindri- 
cal rolls of a dull orange red color. Another form is that of 
lumps or cakes. Its powder is bright yellow and its taste very 
acrid, but it has no smell. It is derived from a tree which is a 
native of Cochin China and Siam, Is used chiefly as a pigment. 



GUMS LINI AND OLIBANUM. i6i 

It is the basis of a general cement in which are also found rubber, 
alum, and burnt sugar, and in another is used with rubber, white 
lead, gum benzoin, alum, sugar, and sulphur, for cementing vul- 
canized rubber. 

Gum Lini. — A gum made from linseed, often used as a sub- 
stitute for gum arable. The seeds are first boiled in water for an 
hour, the resulting thick mass filtered, and then treated with twice 
its volume of 90 per cent, spirits of wine. A flocculent white 
precipitate separates, from which the dilute spirit can readily be 
decanted. The gum is clear, gray brown, fragile, and dissolves 
in water. Two grams in 30 grams of oil is almost identical with 
an emulsion of gum arable. In connection with coloring matters 
is the basis for the Knowlton patented waterproofing process. 

Gum Tragacanth is an exudation which comes in the form 
of translucent plates of a dull white, which water swells and partly 
dissolves. It is often used in mucilage in place of gum arable. 
The gum comes from the Levant from the Astragalus gummifera. 
Has been used in connection with Gutta-percha for making dental 
plates that are soft and adhesive to the membranes and that will 
not rot or deteriorate. 

Gum Lac. — See Shellac. 

Gum Tragasol. — This is a gum produced from the kernels 
of the Ceratonia siliqua. The use of this gum as a solvent for 
India-rubber, Gutta-percha, or celluloid has been patented in 
England. A mixture of 25 parts of dissolved India-rubber, 75 
parts of strong gum solution, with the addition of i part of car- 
bolic acid to 500 parts of the mixture, makes a cement for wood, 
and a preservative paint against insects and vermin. 

Gum Juniper is the gum known as Sandarac, obtained from 
an evergreen growing in northern Africa. It occurs in small, 
light-colored grains, with a slightly bitter taste. It is soluble in 
turpentine oil and alcohol. Is used as an assistant in making 
peroxide substitutes. Mixed with rubber and earthy matters and 
dissolved in turpentine, it was one of the early compounds for 
clothing. 

Gum Olibanum. — The frankincense of the ancients, ob- 
tained chiefly from Asia and Africa. It occurs in yellowish, 
somewhat translucent tears, with a balsam-like resinous smell, 



i62 GUMS AND BALSAMS. 

and an acrid aromatic taste. Sometimes called Gum Thus. It is 
largely used in the manufacture of porous plasters. 

Gum Thus. — A name for gum turpentine, and rarely for 
olibanum. Used with rubber and Japan for waterproofing leather. 

Gum Turpentine. — ^Turpentine hardened by exposure to 
the air. (See Turpentine.) 

Helen ITE. — Another name for fossil rubber or Elaterite 
(which see). 

Isinglass. — A substance prepared from the swimming blad- 
ders of certain fish. It is white and glistening, occurring in fibers 
or threads. The best is known as Russian, and comes from 
Astrachan. Its specific gravity is 1.2. On boiling Isinglass it is 
converted into a very pure form of glue. Isinglass is used in 
quick drying cements with India-rubber, chloroform being the 
solvent. 

Idrialin (Idrialit). — A rare hydrocarbon found in Idria, a 
province of Austria, where it occurs with hepatic cinnabar. A 
similar body is obtained in the distillation of amber. Its specific 
gravity is 1.4 to 1.6. Mentioned in certain rubber formulas to 
assist the insulating qualities of compounds. 

Kauri Gum. — An amber-like substance varying from a soft 
cream white to an amber color. It comes from New Zealand, and 
is also known as Australian dammar. The lighter colored Kauri 
comes from living trees, but much of the darker is a fossil resin. 
It is cheaper than copal and largely used in varnishes. Kauri 
Gum, in connection with rubber gum and pitch, is used for treat- 
ing yams used in insulated wire coverings. Parkes added it to 
rubber goods where the surface was to be printed upon after cur- 
ing. One pound of Kauri, 8 pounds of Gutta-percha, and i pound 
of milk of sulphur formed Richard's covering for insulated wire. 

Lac. — See Shellac. 

Litho-Carbon. — A kind of asphalt large deposits of which 
are found in the State of Texas. It was at one time thought that 
it would supersede India-rubber, and a company was formed with 
the idea of manufacturing goods from it. This was in 1892, and 
India-rubber is still used. The chemical composition of Litho- 
Carbon is 88.23 carbon, 11.59 hydrogen, .06 oxygen, a trace of 
sulphur. Litho-Carbon is jet black in color, is flexible at ordinary 



MAN JACK— MINERAL TALLOW. 163 

temperatures, and is quite tough. Its specific gravity is about 
1.028. It is said to be soluble in naphtha, benzol, bisulphide of 
carbon, etc. It will stand a temperature of 600° F., without giv- 
ing off its associate products. It resists alkalies and acids, with 
the exception of concentrated nitric and sulphuric acids. Its man- 
ufacture was patented. Used with Gutta-percha and shellac it 
makes an excellent insulator. 

Manila Gum. — See Gum Elemi. 

Manjack. — A kind of asphaltum of which there are exten- 
sive deposits in Trinidad, West Indies. Used chiefly in varnishes. 

Mastic. — A resin from the shores of the Mediterranean. It 
occurs in tears of a pale yellow, is brittle, and of a faint balsamic 
odor. It dissolves in acetone, turpentine oil, and alcohol, and is 
largely used in varnish. The residue obtained in the purifying 
of mineral asphalt is also called Mastic. It is used in general rub- 
ber cements for joining stoneware, earthenware, leather, etc. One 
of special value calls for 10 parts of Mastic to i part of India- 
rubber, dissolved in chloroform, and makes an excellent cement 
for fastening letters to glass. The gum also appears in many old 
fashioned compounds. 

Menthol is obtained from the oil of peppermint coming 
from Japan and China, or from the oil of spearmint manufactured 
in the United States. Its melting point is about 108° to 110° F., 
and it is slightly soluble in water, but freely in alcohol. It is often 
tised in medicinal plasters which have rubber for a base. 

Mineral India-rubber Asphalt is the name of a material 
composed of refuse tar produced during the refining process of 
tar by sulphuric acid. It is black, like ordinary asphalt, and quite 
elastic. It is an excellent non-conductor of electricity, and is not 
assailed by acids or alkalies. In a naphtha solution, it yields a 
waterproof varnish for metallic objects, and is used in rubber 
■compounding in place of asphalt. 

Mineral Tallow^ also called Hatchetine, is a substance 
found in Siberia, Germany, and Great Britain. It is an earth wax 
that is soft, flexible, and runs from yellow to yellowish white. 
It has no smell, and melts at from 115° to 170° F, It is com- 
posed of 14 parts hydrogen and 86 carbon. Mineral Tallow is 
used sometimes in place of earth waxes in insulated wire work. 



i64 GUMS AND BALSAMS. 

and has been used in paste blackings in connection with India- 
rubber, 

Mineral Wax. — A term appHed to several waxy-looking 
hydrocarbons found as mineral deposits, such as neft gil (naph- 
tadil), ozocerite, and earth wax. It is found in Austria, and in 
the southern part of Russia, on the shores of the Caspian Sea. In 
the United States it occurs largely in Texas and Utah. Used 
chiefly in insulating compounds. (See Ozocerite.) 

Myrrh exudes from the bark of a tree which grows in Ara- 
bia, in yellow drops that are quite oily at first, but which thicken 
and become hard and of a dark color. It appears in commerce in 
either grains, or tears, or in pieces of various sizes and irregular 
form, the color being red, reddish brown, or yellow. Its taste 
is bitter and aromatic, and its smell balsamic. The best gum is 
known as Turkey Myrrh. It is used with rubber, sulphur, and 
salycilic acid in complexion masks. 

Natural Pitch is the name given to such kinds of pitch as 
are not manufactured, such as asphalt, bitumen, etc, — that is, 
pitch of a mineral origin, except that from coal or shale. (See 
Asphalt.) 

Oleo Resins. — A resin that contains a certain amount of the 
essential oil of the plant from which it exudes is so called. Qiief 
among the Oleo Resins are certain which have a pungent taste 
and a peculiar, and often a pleasant odor, known as balsams. 

Ozocerite. — A waxy hydrocarbon occurring in Austria, 
southern Russia, and the United States. It is also known as earth 
wax. Its specific gravity is 0.9 to 0.95, and it is about as hard as 
talc. Chemically, it consists of hydrogen 13.75 and carbon 86.25, 
while its melting point extends from 140° to 170° F. It is often 
found adulterated with asphalt and sometimes with Burgundy 
pitch. Purified Ozocerite is known as ceresine. To make this, 
the crude material is treated with fuming sulphuric acid, and then 
filtered through charcoal. Thus prepared it is of a pale yellow 
color, the melting point ranging from 61° to 78° C. It has almost 
wholly driven out Stockholm tar as a protection for wires insu- 
lated with Gutta-percha, when placed under ground. It improves 
the insulation, but in spite of common belief to the contrary, does 
not preserve textile fabrics. The best compound for the protec- 



OZOCERINE—PARAFFINE. 165 

tion of the insulation on wire consists of 3 parts of Ozocerite to 
I part of Stockholm tar. It is an insulator of high quality, and 
while it is in some ways intractable, its wax-like nature allows it 
to combine with other insulators or with textiles. It is also used 
as a water-repellent in fabrics, the gum being volatilized by heat, 
and the fumes passed through the cloth. As a surface covering 
for tapes or braid, it is often employed and is better than other 
gums, as it takes a fine polish from the polishing machine. The 
basis of Henley's system of curing India-rubber core is melted 
Ozocerite, which is used under pressure to remove all the moist- 
ure, being afterward heated in hot Ozocerite, which stops up the 
pores. Ozocerite, mixed with India-rubber, is also the basis of 
the India-rubber compound called nigrite. It mixes, however, 
with difficulty with India-rubber, which is an objection to many 
proposed uses of it. It also has a mildly deleterious effect on it. 

OzocERiNE is a vaseline-like substance prepared from ozocer- 
ite. There is also prepared from crude ozocerite a valuable black 
wax which, when fused with India-rubber, makes an excellent 
electric insulating material. This wax was recognized by a lec- 
turer before the Society of Chemical Industry as the basis of the 
insulation known as Okonite. 

Paraffine. — A white waxy-looking body obtained from Pe- 
troleum and certain tars by distillation. It is tasteless, inodorous, 
harder than tallow, but softer than wax. Its specific gravity is .877. 
It is also obtained from ozocerite or earth wax. Its melting point 
varies with the source it is obtained from. It is insoluble in water 
and nearly so in boiling alcohol, but soluble in ether, oil of tur- 
pentine, oil of olives, benzol, and bisulphide of carbon. It is 
usually very free from water, and not liable to absorb it. It has 
been used as a waterproofing mixture and is a good insulator. A 
very widely difiFused bit of newspaper advice has been that to pre- 
serve rubber goods they should be dipped in a bath of melted 
Paraffine and dried then in a hot room. It has not been proved 
to be of any advantage, however. Experts in the rubber trade 
claim that such a course would seriously injure the elasticity and 
life of the rubber. When gossamer clothing was manufactured 
in large quantities, the surface of the goods before solarization 
was covered with a thin coat of Paraffine, which gave it a peculiar 



i66 GUMS AND BALSAMS. 

shade until the solarization was completed, when all traces of the 
Paraffine seemed to disappear. The insulating capacity of rubber 
to which Paraffine has been added is quite remarkable, but at the 
same time it lessens the hardness of the rubber to a marked degree. 
Rubber dissolved in Paraffine wax forms a curious compound 
which has been used in insulation. Paraffine is used in the arti- 
ficial gums like Parkesine and insulite; also with cottonseed oil 
and resin for cheap Brattice cloth, and in cheap proofing com- 
pounds. It is not a great favorite as an insulator, as it shrinks 
in cooling, causing cracks. Paraffine tapes are also easily de- 
stroyed through the presence of free acid. It was formerly used 
largely in covering annunciator wires, but as it was found to 
absorb and retain water, its use was given up, and its place taken 
by a compound of Paraffine, ceresin, and resin. 

Pitch is the black residue that remains after the distilling 
of wood tar. Varieties are also obtained from coal tar and from 
bone tar. Wood pitch, however, has a toughness which the others 
do not possess. Pitch was used very early in considerable quan- 
tities in hard-rubber compounds. Goodyear, for example, used 
considerable of it in hard compounds for coating metal, the rest 
of the compound consisting chiefly of rubber and sulphur. It is 
almost the only organic substance which largely increases the 
resiliency of India-rubber. It is largely used in cements, and also 
in many rubber compounds. Equal parts of pitch and Gutta- 
percha make a tire cement for fastening to the rims, known as 
"Davy's Universal Cement." It is used with Gutta-percha in 
shoemakers' wax, and also in certain proofing compounds. Wood 
cements made of Gutta-percha as a rule contain a certain amount 
of Pitch. It is also used in the manufacture of Fenton's artificial 
rubber. 

Resins. — The term given to a number of complex bodies, 
generally the hardened exudation of sap from trees. Chemically 
a resin is the substance obtained by the gradual oxidation of an 
essential oil. The specific gravity ranges between 1,02 and 1.2. 
Resins are divided, as a rule, into three classes — hard, soft and 
gum resins. The former at ordinary temperatures are solid and 
quite brittle. They contain little or no essential oil, and are easily 
pulverized. Shellac and sandarac are good examples of this kind, 



RETINITE— ROSIN. 167 

and soft resins are usually called balsams, and are either semi- 
fluid, or soft enough to be molded by hand. They are really mix- 
tures of hard resins, and the essential oils found in the plant from 
which they come. On exposure to the air they become in time 
hard resins. Of this class are balsam of storax, tolu balsam, etc. 
Gum resins are the solidified milky juices of certain plants. They 
consist of a mixture of resins, essential oils, and a considerable 
proportion of gum. These are, for example, gum euphorbium, 
galbanum, and to this class also belong India-rubber and Gutta- 
percha. Most of the fossil gums, such as copal, are resins whose 
physical characteristics have been changed by their having been 
buried for a long time in the earth. These fossil resins are coun- 
terfeited to an extent by treating ordinary resin with lime, which 
raises its melting point considerably. 

Retinite. — Also known as Retin Asphalt. It is a fossil resin 
found in brown coal. It is found in roundish masses of a yellow 
brown or reddish color, is quite inflammable and readily dissolves 
in alcohol. At present it is somewhat rare, but if it ever should 
become common, it would undoubtedly find a place in rubber 
compounding. Its specific gravity is 1.07 to 1.35. 

Rosin is made from common turpentine, which is distilled 
in water, yielding nearly one-fourth its weight of essential oil, 
the residue in the retort consisting of common rosin. Rosin is 
also very generally called colophony, its true chemical name 
distinguishing it from other resins. There are two varieties 
of rosin in common use, the brown and the white. The 
first named is brittle, solid, and of an amber color, and comes 
from the Norway spruce fir. The white rosin is obtained from 
the pine and is known as galipot. Rosin dissolves very 
freely in alkaline solutions, which allows of its use in soaps. Its 
specific gravity is 1.08. There are three grades commonly on 
the market, which are called virgin, yellow dip, and hard. It is 
used in a great variety of rubber compounds, its chief uses being 
in frictions, dry heat varnishes, cements, and the puncture fluids. 
Almost all lines of rubber manufacture use a certain amount of it 
at times. Only a small proportion of it can be used in rubber 
compounding, its office being usually that of the sticker. A large 
amount of it induces surface cracking, and often a decided bloom- 



i68 GUMS AND BALSAMS. 

ing of the sulphur. It is also used in waterproof solutions in con- 
junction with spermaceti, India-rubber, and paraffine wax. Mixed 
with boiling oil, it has been applied to Gutta-percha articles to give 
them a Japan-like luster, and is also important in Gutta-percha 
glue, which is compounded of Gutta-percha, powdered glass, lith- 
arge, and Rosin. A very large use for it is in the rubber channel 
cements that are sold to leather shoe manufacturers. 

Sandarac. — Also known as Gum Juniper (which see). 

Seedlac. — See Shellac. 

Shellac, Sticklac, Seedlac, Gumlac. — All these are dif- 
ferent names for the same thing or different stages of its prepara- 
tion. It is the exudation formed on several sorts of trees growing 
in the East Indies, but is chiefly produced from the banyan tree, 
the exudation coming from a scale shaped insect known as the 
Coccus lacca, the female fixing herself to the bark and exuding 
the resinous substance from her body. In addition to the East 
Indian product there is what is known as Mexican lac, which ex- 
udes from the Croton draco. Sticklac is the resin as taken from 
the tree. Seedlac consist of fragments broken from the twigs and 
partly exhausted by water. Shellac is prepared by melting Stick 
or Seedlac, straining, and pouring upon a flat surface to harden. 
It is. then washed, dried, melted, roughly refined, and sent to mar- 
ket, or it is poured into molds to harden and is known as Button 
or Garnet lac. The specific gravity of Lac is about 1.139. It is 
partially soluble in alcohol, turpentine, chloroform, and ether, and 
is completely soluble in caustic alkalies and borax solutions. Shel- 
lac was formerly used very generally in rubber manufacture in 
surface goods, and particularly in solarized goods in small pro- 
portions. It has a specific use to-day in the production of water 
varnishes for surface goods. It is also a constituent in the pro- 
duction of certain compounds in hard rubber, and particularly 
the semi-hard varieties, being used to the extent of 20 per cent, 
of the amount of gum. Although quite brittle, it seems to impart 
a certain elasticity to the product. The maximum use of Shellac 
in a hard-rubber compound, according to Hoffer, is 88 parts India- 
rubber, 50 parts Shellac, and 12 parts sulphur. It is also used 
in certain of the Jenkins patented packings to the extent of 10 to 
25 per cent, of the amount of rubber, where it is said to preserve 



SIZE—STEARINE. 169 

the compound from the effects of coal oil, steam, or hot water. 
It is also used in many cements both with and without India- 
rubber, one formula for marine glue being: 20 parts shellac, 12 
parts benzol, and i part India-rubber mixed with heat. Dis- 
solved in 10 parts of strong aqua-ammonia, it forms a varnish 
for rubber goods, and is also used as a solution for re-varnishing 
old rubber shoes. Used with carburet of iron and bisulphide of 
mercury as a cement for card clothing, with India-rubber and 
Gutta-percha for attaching shoes to horses, in English "ale 
cement," and in certain proofing compounds. 

Size. — A weak solution of glue, sometimes used in shower- 
proof compounds and cements. The name Size is also often 
applied to any thin viscous substance, as for instance, gilders' var- 
nish. In rubber practice, however, the glue Size is what is 
ordinarily employed. It is also used in perparing a perfectly 
smooth cloth upon which rubber is to be calendered, and from 
which it is stripped before the making up. (See Glue and 
Gelatine.) 

Spruce Gum is used with chicle in the production of chew- 
ing gums. Melted spruce gum or rosin is known as Burgundy 
pitch (which see). 

Stearine. — A white waxy-looking body obtained from fata 
— chiefly tallow and palm oil. When made from tallow it is 
called pressed tallow or tallow Stearine, which is the solid part 
obtained from the heating of suet fat and the removal of the 
liquid part which is oleomargarine. Tallow Stearine is very 
largely used in candle making, where is found saponified Stearine, 
distilled Stearine, and distilled grease Stearine. This latter con- 
tains considerable cholestrol and differs from commercial stearic 
acid or Stearine chiefly in its physical structure. Stearine is used 
in proofing compounds, in rubber blackings and in compounds 
containing resins. It has been suggested that a small proportion 
of Stearine in certain rubber compounds that contain low grades 
of rubber which in themselves have large proportions of resin, 
has a decided value in preventing oxidization. 

Stearine Pitch. — The brown tarry residue left in the still 
during the process of refining tallow and fat. Used in the manu- 
facture of certain packings that contain no rubber. Stearine 



170 GUMS AND BALSAMS. 

Pitch is also used as a lubricant for bearings that have a ten- 
dency to heat. 

Stick Lac. — See Shellac. 

Stockholm Tar is used in black cements of the marine glue 
class, and is also used in rubber compounding, its office being to 
assist in the mixing of dry compounds, and as a binding material 
for sulphur in the dry heat cure. Also used in manganese 
cements and in cements to fasten tiles to floors. (See Tar.) 

Spermaceti. — A peculiar fatty concrete substance obtained 
from the head of the sperm whale. Its specific gravity is 0.943, 
and it is fusible at 112° F. Insoluble in water, soluble in hot 
alcohol, ether, and oil of turpentine, but redeposited as the liquids 
cool. Was formerly used in certain waterproofing compositions. 

Sludge Oil Resin. — A heavy gummy residue from the 
waste of superphosphate factories. Has been used with rubber 
in making Japan varnishes. 

Tar. — This substance is derived from the animal, vegetable, 
and mineral kingdoms. From the first, by the destructive distil- 
lation of bones, is produced what is known as "Dippel's oil"; 
from the second, by the distillation of pine woods, the product is 
known as pine tar or Stockholm tar ; and from the third, by the 
distillation of coal, is produced coal tar. Of the three, coal tar 
is the most used in rubber work, its office being to help carry 
adulterants in dry mixing and to keep the sulphur from blooming 
after vulcanization. It is used chiefly in dry heat work. Good- 
year discovered early that very large quantities of boiled tar 
could be used in connection with India-rubber and sulphur with- 
out injuring the quality of the gum, and it has been very generally 
used since his time. 

Trinidad Asphalt is obtained from the pitch lakes of the 
island of Trinidad. Its specific gravity is 1.2, and it is somewhat 
soluble in alcohol, while Persian naphtha, oil of turpentine, benzol, 
and benzoline readily dissolve it. (See Asphalt.) 

ToLU Balsam is derived from a tree found on the mountains 
of Tolu, and the banks of the Magdalena river, in Colombia. It 
is very similar to balsam of Peru. It sometimes appears in com- 
merce in dry friable fragments, the newly imported gum being 
soft and tenacious. It has a very fragrant odor, and a medicinal 



VEGETABLE PITCH— XYLOIDIN. 171 

and tonic effect. Tolu Balsam is used with paraffine wax and 
chicle in chewing gum compounds. 

Turpentine. — This is a semi-solid resin, which comes from 
various species of pine as a rule. The chief commercial varieties 
are common Turpentine, which comes from the Pinus palustris; 
Venice Turpentine, from the larch; Bordeaux Turpentine, from 
the Pinus maritima, and Qiina Turpentine, from the Pistacia 
lentiscus. Of these the Venice Turpentine is said to be the best. 
It is of a pale yellow color, transparent, has a bitter taste, but a 
balsamic odor. Used instead of rosin in many compounds. 

Vegetable Pitch. — The residue left after distilling the tar 
made from wood of various trees. Called vegetable to distin- 
guish it from the mineral pitch which is derived from coal. (See 
Pitch.) 

Xanthorrhoea Gum is somewhat similar to shellac, is 
abundantly produced in the Australian colonies, and sometimes 
used in the compounding of ebonite. Xanthorrhoea Gum is also 
sometimes known as gum acaroides, and is produced from the 
Australian grass tree. 

Xyloidin. — An artificial gum much resembling pyroxylin 
obtained by the action of nitric acid on starch. 

Xylonite. — See Zylonite. 



CHAPTER IX. 

PIGMENTS AND PROCESSES USED IN COLORING INDIA-RUBBER. 

Most of the India-rubber goods now manufactured are 
black, this color, if it may be so called, being produced in a 
measure by the color of the rubber, together with the leads and 
other ingredients, most of which darken during vulcanization. 
The next prominent color, from a rubber standpoint, is white, 
produced by either an oxide or sulphide of zinc. Next to this 
range the yellows and reds, produced by the use of sulphide of 
antimony and vermilion. 

So many colors are unstable when brought in contact with 
sulphur during the heat of vulcanization, and it is so difficult to 
get good effects, that it is hardly to be expected that beautiful 
colors in India-rubber will ever become common. There are 
various methods used for changing the natural color of India- 
rubber. The usual way is by incorporating, by mechanical mix- 
ture, earthy pigments or metallic oxides or sulphides, or vegetable 
coloring matters, which, by their covering property and strength, 
give to the India-rubber their own particular shade. There are 
other methods, however. For example, there have been produced 
anilines soluble in benzine, that are used for surface work, such 
coloring being really an elastic enamel. Toys and minor articles 
that are ornamented in very bright colors, however, are generally 
painted over after vulcanization, but paint is not durable, nor 
does it long remain beautiful. 

While it is claimed ordinarily that it is impossible to dye 
India-rubber, it should be remembered that the attractive colors 
that appear on childrens' toy balloons and similar pure gum goods 
are applied as dyes, the colors being anilines, with methylic alco- 
hol as a base. These colors are boiled in rainwater, and when the 
solution is cold the balloons are put into the coloring liquid and 
turned so as to have their entire surface wetted. After that, they 
are dropped into cold water, which washes off the superfluous 
color. When this is done properly, the rubber does not give off 
any stain at all after the first washing. The colors used in this 

172 



ANILINE COLORS. 173 

way are red, green, blue, orange, and pink, but other shades are 
equally available. 

In Germany a full line of aniline colors soluble in benzine 
is now manufactured, and for surface coloring of rubber goods 
they have been found very valuable. Although they are not abso- 
lutely fast, they are sufficiently so for all practical purposes. In 
many cases, these aniline colors, being soluble in benzine, can be 
mixed right with the India-rubber — that is, when it is used in the 
form of solution. If the product be cured in open steam heat with 
sulphur, some very curious effects are likely to be obtained. This 
was proved at one time when a line of rubber colors was put 
on the market in the United States, with white oxide of antimony 
as a base, and anilines to give various shades. It does not often 
happen, however, that a problem of this kind confronts the users 
of aniline colors in rubber, the more general and sensible way 
being that of surface coloring. This is done in some cases by 
simply brushing the aniline color dissolved in benzine over the 
surface of the article. It is desirable, however, first to dip the 
goods in the dissolved mordant, and then to use the brush, if 
necessary. Where a high polish or a polished effect is desired, 
some sort of elastic lacquer must be put on over the coloring mat- 
ter. A very thin India-rubber solution is often used for this. 

In speaking of anilines, it must be remembered that those 
that have to be worked up with acids should be avoided for rub- 
ber work, but there are so many others that there is no need of 
the rubber man making this mistake. Where colors are to be 
printed upon rubber surfaces, a little dextrine is added to the ani- 
line dissolved in benzine, and to make the color dry faster, a little 
sulphate of manganese mixed with half of i per cent, of alum and 
added to the mass is advisable. 

Black, blue, red, yellow, and green anilines are also used in 
coloring rubber cements that go to the leather shoe trade. These 
and other anilines are also used very generally in artificial leather 
compounds. Aniline, black, is used in water varnishes for luster 
coats and blankets. 

It is also a good idea to sponge the rubber surface with a 
water solution of alum before the color is applied. The use of 
alum as a mordant may be supplanted by bisulphate of soda, if it 



174 COLORING MATTERS AND PROCESSES. 

is desired. The best colors available in the aniline series are reds, 
particularly magenta reds, and the marine and alkali blues. 

A great many methods of surface coloring have been devised, 
some of them being ludicrous attempts at dyeing rubber. The 
surface of rubber is, of course, not easily affected by colors, 
unless it has first been attacked and roughened by some powerful 
solvent. Malcolm's process for this surface coloring is perhaps 
as harmless as any. This method is to expose the rubber to the 
sunlight while it is immersed in alcohol. When the surface is 
somewhat disintegrated, the rubber is taken out, washed, and 
dipped in a dye solution. 

The colors that follow are described very briefly, and most 
of them are such that any rubber manufacturer can easily secure 
them for use or for experiment. 

WHITE. 

Only a few colors are available for use in making white 
rubber goods. Of these, the zincs take the lead, being by far the 
most constant and valuable. They lend their color to the mass 
simply by their presence as dry paints with strong coloring 
qualities. 

Barium White. — This is also called constant white, and 
comes from the sulphate of barium or heavy spar. In treatment, 
it is ground very fine, treated with hot hydrochloric acid, washed, 
dried, sifted, and then forms a fairly white, dense, impalpable 
powder. The pure article, obtained by precipitation, is a brilliant 
white, and is often used in rubber compounding. It is one of the 
few metallic colors that the German anti-poison act allows manu- 
facturers to use in any way they please. (See Barytes.) 

Beckton White. — See Lithophone. 

Borate of Zinc. — A zinc salt, precipitated by 20 to 30 per 
cent, of a soluble borate, the result being a white powder, which is 
claimed to have a distinctively preservative influence when used in 
rubber, while the tensile strength of the gum is much enhanced. 

BouGiVAL White was a fairly common white pigment, 
although it has been replaced by barytes, terra alba, and whiting. 
Bougival White is a white, marly, china clay found at Bougival, 
near Marly, in France. The district surrounding Bougival and 



WHITES. 175 

also Normandy and Auvergne contain many beds of white clays, 
notable for their smooth qualities of good color. Roughly Bougi- 
val White contains 33 per cent, chalk (carbonate of lime) and 67 
per cent, kaolin (hydrated silicate of aluminium). 

Calamine White. — This is prepared from the native car- 
bonate of zinc, by calcining and grinding. It is not a strong 
white, and is not nearly as good as the oxide or carbonate of zinc 
as a coloring matter. For a cheap white, and a filler, however, 
it is useful. Although the German anti-poison act of 1887 pro- 
hibits the use of zinc as a coloring matter, it does not apply to its 
ordinary use in rubber compounding. They rule that zinc com- 
pounds not soluble in water may be used in rubber when and 
where the coloring matter is mixed in the mass before vulcan- 
izing, or as a color laver on the surface if it is covered with a 
lacquer varnish. 

Carbonate of Zinc. — This is a form of zinc rarely known 
to-day in rubber mills. The first white rubber, however, was 
made of it under a patent granted to that eminent rubber manu- 
facturer, the late Henry G. Tyer. It is a white powder, and is 
made by mixing a solution of equal quantities of sulphate of zinc 
and carbonate of sodium, and subsequently the boiling of the 
white precipitate formed for a short time. 

Charlton White. — See Lithophone. 

Fard's Spanish White.: — Also known as Pearl White. A 
tri-nitrate of bismuth, and a white that, it is said, has a future in 
rubber compounding. It is not easily affected by atmospheric 
influences, or by the action of sulphurous compounds. 

Fulton White. — See Lithophone. 

Griffith's White is a sulphide of zinc of English manu- 
facture, prepared by precipitation, and containing a certain pro- 
portion of magnesia, 

Kremnitz White was the name of a somewhat indefinite 
white. In some cases it was applied to white lead, but in others 
was given to bismuth white (oxide of bismuth) and often to 
white oxide of tin. 

Lithophone (also Lithopone). — A white pigment made by 
precipitating sulphate of zinc with barium sulphide. The barium 
sulphide is made from the native barites by heating with charcoal, 



176 COLORING MATTERS AND PROCESSES. 

which reduces the sulphate to sulphide and polysulphide, which 
are soluble in water. The zinc sulphate is made by roasting zinc 
blende or the ore "black jack" under oxidizing conditions, which 
forms soluble sulphate of zinc. Both substances are dissolved in 
water, which purifies them from many impurities, and the two 
solutions mixed, when zinc sulphide and barium sulphate both 
precipitate out as fine powder mixed with free sulphur from the 
polysulphide. The powder is dried and roasted, which drives off 
free sulphur and produces some free zinc oxide. Gives a fine 
white; but may turn gray on long exposure to light. This 
defect not so bad for rubber as for painting. It is a constant 
white, and is largely used instead of oxide of zinc for white 
goods, particularly in the manufacture of druggists' and surgical 
sundries. The commercial article contains 70 per cent, of Barium 
sulphate and 30 per cent, sulphide of zinc. Its specific gravity is 
3.6 to 4.1. 

MouDAN White or Morat White. — This white came from 
the Pays de Vaud in Switzerland, Moudan and Morat being two 
towns in that district. It was a fine white clay with a silky 
luster and a fine grain. They resembled Spanish white and were 
often used in place of it. 

Oleum White. — A high grade of sulphide of zinc, in which 
is a certain proportion of blanc fixe. It is a trifle heavier than a 
pure sulphide of zinc, but in practice has been found to be equal to 
if not better than either the sulphide or oxide of zinc in the manu- 
facture of certain white rubbers. 

Orr's White. — See Lithophone. 

Oxide of Zinc is used more than any other coloring matter 
in the production of white rubber. It is especially valuable be- 
cause during the process of vulcanization it increases the white- 
ness of the goods. This is because the part of the zinc oxide that 
is turned into the zinc sulphide is a stronger white than the first. 
Oxide of Zinc made of pure spelter is the best. Where lead and 
zinc ores are found together it sometimes happens that the oxide 
contains a certain amount of lead, and then its value as a coloring 
matter is injured. It is prepared by two processes, an air blast, 
and a steam current ; in other words, by a dry and a wet process. 
That prepared by the wet process, even when strongly heated. 



WHITES. 177 

contains more water than does that produced by the dry process. 
The specific gravity of zinc oxide is 5.61. A certain percentage 
of this oxide is often added to dark colored goods to increase the 
resiliency of the rubber. It also increases the hardness of a 
compound where soft gums are used. Manufacturers of insu- 
lated wire find that it increases the insulating qualities of rubber 
when added in moderate quantity. 

A very simple test for zinc oxide is as follows : Put a small 
quantity in a test tube or vial and add diluted muriatic acid 
(such as can be obtained in any drug store) ; agitate to dissolve 
all lumps, and if it be commercially pure oxide of zinc, no residue 
will remain. The only adulterant likely to be found which would 
not leave a sediment would effervesce violently. Should the 
addition of acid to the pigment produce sulphureted hydrogen, 
the odor of which is unmistakable, no doubt would exist that the 
sample is not oxide of zinc and probably a much cheaper pig- 
ment. There are many pigments on the market called zinc and 
containing some zinc in various forms, which have their uses, but 
should not be confused with straight oxide of zinc. 

Ross's White. — See Lithophone. 

Rouen White was a marly clay found near Rouen in 
France, prepared for use by levigation. In most respects it 
resembles Bougival white. 

Spanish White is a name often now given to a good quality 
of whiting, but originally given to a good kaolin clay prepared 
for sale by first levigation, then treatment with vinegar, which 
separated out any calcium carbonate it contained, then washing 
well and drying. 

Sulphide of Zinc. — This is a white that is fully equal to the 
popular oxide, and does not alter its tint under the influence of 
sulphur and heat. It is said to exert a distinctly preservative 
action upon India-rubber. Sulphide of zinc, pure and in combina- 
tion with other materials, and under various names, has been sold 
very largely to rubber manufacturers. It is deemed especially 
valuable in white goods cured with dry heat. It is used in high 
grade white stocks, and even in pink dental rubber. It also assists 
in the vulcanization of rubber. 

Troye's White is a carbonate of lime, and, therefore, was 



178 COLORING MATTERS AND PROCESSES. 

in all respects like the modern whiting. It was a very common 
pigment at one time and much used for a variety of purposes. 
Zinc White. — See Oxide of Zinc. 

BLACK. 

There are more methods of getting black rubbers than 
almost any other color, as the tendency of the gum itself is to 
darken under heat and the action of sulphur, and the sulphides of 
most materials that are used in the compounding have the same 
effect. Most rubber goods are made up without regard to 
color, and are usually a dirty brownish-black, tempered by the yel- 
low of the sulphur bloom. Where a genuine black is wanted, 
however, some of the vegetable blacks or perhaps certain of the 
leads are employed. Lampblack is one of the most common in- 
gredients used. 

Lampblack. — Pure Lampblack is pure carbon, as indeed is 
the diamond. Lampblack, however, is carbon in its amorphous 
or spongy form, while the diamond is crystalline. It is obtained 
on a large scale by collecting the smoke produced during the 
combustion of oils, fats, resins, coal, gas, tar, wood tar, petroleum 
residues, dead oil, and even bituminous coal. This accounts for 
the various grades that are to be found on the market. Large 
quantities of Lampblack have also been manufactured from 
natural gas. There are many types of Lampblack, the best in 
the world being employed in the preparation of Indian ink. This 
is made from burning camphor, a lower grade being made from 
the mixture of camphor and other oils. The smoke is collected 
on leaves, washed, dried, and sifted with the utmost care. The 
lines of rubber goods in which it is generally found are rubber 
boots and shoes, surface clothing, and carriage cloth, druggists' 
sundries (where the leads are deemed dangerous), and in certain 
compositions where emery is the chief ingredient used for grind- 
ing or polishing. A curious fact about Lampblack is that a little 
bit of it in unvulcanized erasive rubber seems to assist the 
erasive quality, and does not cause smutting. A little of it is also 
sometimes added to churning mixtures that do not readily mix. 
The following analysis of the composition of lampblack is given 
by Braconnot: 



BLACKS. 179 

Carbon 79.1 

Water 8.0 

Resinous matter 5.3 

Bituminous matter or pitch 1.7 

Sulphate of ammonium ^.^ 

Sulphate of calcium .8 

Sulphate of potassium 4 

Chloride of potassium traces. 

Phosphates of calcium and iron .3 

Siliceous or earthy matter i.i 

Total loo.o 

The analysis of lampblack from a large black manufactory 

in the United States: 

Carbon 79.1 

Empyreumatic resin \ ^^^^^'^^.^ --_■■ ^ 

Humin 0.3 

Sulphate of ammonium 3.3 

Sulphate of lime 0.8 

Sulphate of potash 0.4 

Phosphate of lime 0.3 

Water 8.0 

Chloride of potassium trace only. 

Sand (accidental) 0.6 

Total lOo.o 

BoNEBLACK, also Called animal charcoal and sometimes ivory 
black, is a black powder obtained by grinding the product of 
bones that are burned at a red heat in close vessels. It resembles 
vegetable charcoal, but is more dense and less combustible. A 
good quality should have an even color, of a rather dull shade. 
On analysis, boneblack shows the following : 

Phosphate of lime 78.0 

Phosphate of magnesia 1.5 

Carbonate of lime 8.5 

Carbon lo.o 

Impurities, silica, iron, etc 2.0 

Total lOO.o 

Sulphide of Lead. — This is a valuable coloring matter for 
rubber, as it gives a good black, besides which it makes goods 
exceedingly resilient. There are great differences in the pro- 
duction of lead sulphides, but, as before remarked, a good one 
is of special value to rubber manufacturers. (See Leads.) 

Mineral Black is a pigment that is said to be made from 
l)ituminous lignite. It is very porous, and is not recommended 



l8o COLORING MATTERS AND PROCESSES. 

for rubber work. A very little ultramarine blue added to a black 
in rubber sometimes overcomes the grayish shade. 

Sulphide of Uranium. — A fine black pigment more intense 
than plumbic blacks. It is a permanent color, and is said to be a 
preservative of rubber. 

Black Hypo. — This is also known as hyposulphite of lead. 
It is really a mixture of thiosulphate of sodium mixed with 
acetate of lead, and appears as a fine white crystalline precipitate, 
which should be called thiosulphate of lead. There are two forms, 
the white hypo and the Black Hypo, the difference being that the 
white when heated is transformed into a soft black powder con- 
taining very little free sulphur. The black of the compound 
being sulphide of lead often contains over 90 per cent, of pure 
sulphide. It is an excellent vulcanizing agent, and also a filler. 
When properly prepared it makes goods absolutely free from 
bloom. 

Carbon Blacks of late have been used very largely in rubber 
compounding and have done excellent work. They are not as 
black, as a rule, as the better grades of lampblack made from 
oils or resin. They are in many cases wholly inert, however, 
and therefore perfectly safe to use. One of the best types of 
this sort of coloring matter comes from a graphite mine in the 
United States. It is wholly amorphous, and has none of the flaky 
make-up that ordinary graphite has, and is 97 per cent, pure car- 
bon. Carbon Blacks, it is also said, give a brighter finish to var- 
nished goods than ordinary lampblacks. 

Oak Black. — A product of the distillation of oak wood after 
draining off (i) wood alcohol and (2) a product resembling tar. 
It is used in certain black insulating compounds in connection 
with shellac, coal tar, paraffine, and asbestos. 

BLUE. 

Blues are not largely used in general rubber work. They 
are found chiefly in toys, in sheetings, and in certain packings. 
The most important blue is — 

Ultramarine. — This is made from lapis lazuli. The exact 
composition of this coloring matter is not known, but it is said to 
be based on a silicate of alumina with sulphide of sodium. An 



BLUES. i8i 

artificial ultramarine is often produced which is equal and often 
superior to the natural pigment. This is made of kaolin, carbon- 
ate of sodium, willow charcoal, and sulphur. The following 
analysis of the natural Ultramarine is given: 

Silica 37-6 

Alumina 27.4 

Sulphur 14-2 

Soda 20.0 

Analyses of the best artificial Ultramarines show these figures : 

Silica 40.25 39-39 40.19 

Alumina 26.62 24.40 25.85 

Sulphur 13.42 12.69 13.27 

Soda 19.89 21.52 20.69 

Ultramarine appears in commerce as a fine blue powder of 
various standards of fineness. Acids readily destroy it, but alka- 
lies have no effect on it. It stands heat well, not changing below 
a low red. It is used in cements for backs of memorandum 
blocks, and in blue soft rubber goods, particularly in vapor cured 
goods, such as sheeting. When mixed with chrome yellow it 
makes a green; with colcothar, it makes a violet. Mixed with 
rose pink, oxide of zinc, and Indian red, it produced the well- 
known wine-colored coat that was so popular a few years ago. 
It is claimed that Ultramarine blue keeps rubber from overcuring, 
and that it is, therefore, a most useful ingredient to add to com- 
pounds that are exposed to heat. 

Yale Blue. — In certain soft rubber goods, where a strong 
blue is needed, ultramarine was found unsatisfactory. A firm of 
rubber chemists therefore produced Yale Blue, which is a strong, 
coloring matter, and wholly inert as far as the rubber is 
concerned. 

Smalts. — This is what may be called a deep tinted cobalt 
glass. The analysis of Smalts of good quality is as follows: 

Deep Pale 

Colored Colored 

Norwegian German 

Silica 70.9 72.1 

Potassa (with traces of soda and lime) 20.4 20X) 

Oxide of cobalt 6.5 2.0 

Alumina .4 1-8 

Peroxide of iron .3 1.4 

Other earths and oxides, and loss 1.5 2.7 

Total loo.o loo.o 

This is one of the few colors that are practically indestruct- 



i82 COLORING MATTERS AND PROCESSES. 

ible. In using Smalts for the pigment, large quantities are nec- 
essary, as the color is not exceedingly strong. 

Cobalt Blue is manufactured from oxide of cobalt, phos- 
phate of cobalt, and alumina. It is rarely used in coloring rubber 
where the ingredients are to be mixed with the mass, ultramarine 
being much superior. Also called Smalts. 

Thenard's blue is similar to cobalt blue, but is a more beauti- 
ful pigment. It is used chiefly as a surface color. White pig- 
ments in small quantities added to this blue make beautiful tur- 
quoise colors. 

Prussian Blue. — A dark brilliant blue compound, having 
iron for a base. There is a soluble and an insoluble variety of 
this compound which is of a somewhat complex chemical con- 
stitution. Heated strongly in the air, the insoluble form of Prus- 
sian Blue burns like tinder. When boiled with caustic 
potash, it is decomposed. If the dry powder be strongly rubbed 
in a mortar, it assumes a copper red luster. In commerce it 
occurs in irregular shaped masses, having a characteristic con- 
choidal fracture and copper red luster. 

Chrome Blue is manufactured from silica, fluor spar, and 
chromate of potash. The resultant material is a deep blue 
vitreous mass which is reduced to an impalpable powder. It is less 
sensitive to acids than ultramarine, and is better adapted for 
r|3bber goods. 

Saxon Blue is the original name of the pigment known 
to-day as smalts ; it was also very frequently called enamel blue. 
Under this name was also sold a blue pigment made by mixing 
Prussian blue with alumina or a white clay. 

Molybdenum Blue. — A pigment recommended by Lascel- 
les-Scott is a bisulphide of molybdenum. It is an exceedingly 
beautiful blue, but costly. Large new deposits of this mineral 
have been found in the United States and Australia, and Norway, 
and it is likely to be so cheapened that it will be a valuable rubber 
pigment; 

Indigo Blue is prepared from plants of the Indigofera genus. 
Pure Indigo is insoluble in water, nor is it soluble in weak acids 
or alkalies. A small percentage is dissolved in alcohol and its 
solution is more considerable in turpentine. Indigo Blue for rub- 



REDS AND BROWNS. 183 

ber is said to be valuable on account of its preserving qualities, 
which are double those of other blues. 

RED AND BROWN. 

The strong red coloring matters used in rubber work are 
mostly of a mercurial base. These are vermilion, red chromate 
of mercury, sulphide of mercury, and iodide of mercury. The 
Chinese vermilion, which is the best, is prepared by a special pro- 
cess of their own, and contains 89 per cent, of pure mercury, the 
rest being sulphur. This coloring matter is used very largely in 
dental vulcanite, small amounts of it also giving excellent shades 
in soft rubber goods. Cinnabar and Paris red are also mercurial 
sulphides, and very strong colors. The sulphides of mercury 
are really the only ones that are safe and valuable for producing 
these colors. Red chalk and natural clay containing a certain 
amount of iron are used chiefly as fillers in rubber goods, 
although a certain quantity of them produce a dark red color. 

Vermilion. — The red form of mercuric sulphide is a scarlet 
red powder of specific gravity 8.124. It is sometimes adulterated, 
with red lead or red oxide of iron, but such adulterations can be 
detected by heating a small sample of the suspected article on a 
porcelain or platinum dish. If any adulterant is present it will 
remain behind as a residue, since pure Vermilion is completely 
volatile. This substance is sometimes called cinnabar. A substi- 
tute for Vermilion in; hard rubber was brought out by John Hali- 
dayin 1870. This was a mixture of garancine and cochineal, in 
water solutions, boiled and mixed in the proportion of 5 parts of 
garancine liquor to i part of cochineal liquor. To each gallon 
of this compound liquor 2 pounds of pure oxide of antimony were 
added ; ■ then heating until the water was evaporated and the 
new coloring matter perfectly dry. Another substitute for ver- 
milion was white oxide of antimony. According to A. D. Schles- 
inger, the veteran of hard rubber experts, white oxide of anti- 
mony, when mixed with India-rubber and sulphur, will, during 
vulcanization, impart to hard rubber a light red color very similar 
to that obtained by the use of Vermilion, The proportion of sul- 
phur is the same as is used ordinarily in making vulcanite, while 
to-each pound of rubber are added 12 ounces of antimony sulphide. 



i84 COLORING MATTERS AND PROCESSES. 

Red Oxide of Iron. — This is familiar as iron rust. The best 
is artifically prepared from green vitriol iron sulphate, and forms 
a scarlet powder of a specific gravity if 4.46. This contains about 
5 per cent, water of crystallization, which cannot be driven off at 
temperatures up to 212° F., and with difficulty at higher ones. 
(See Colcothar.) 

Peroxide of Iron. — An old name for the sesquioxide of iron, 
now called ferric oxide. (See Oxide of Iron.) 

Prince's Metallic Paint. — An oxide of iron. 

Indian Red. — Another name for oxide of iron. 

Red Hematite. — An ore of iron, somewhat soft and friable. 
Specific gravity 5.19 to 5.28. Composition 70 per cent, iron, 30 
per cent, oxygen. Insoluble in water, alcohol, or rubber solvents. 
As a colorant in rubber work it is unchangeable chemically. Used 
in packings and for red maroons. 

Venetian Red. — See Colcothar. 

Red Ocher. — An impure oxide of iron. A dull red earthy 
substance containing clayey matter, and having a specific gravity 
of about 5.2. Used chiefly as a filler, as the color is not strong. 
As far back as the time of Dr. Mattson, Red Ocher, Venetian red, 
and Indian red, were advised by him for use in rubber com- 
pounding. Indeed, he obtained a patent for packing in which 
Venetian red was the principal adulterant. 

Orange Vermilion gives a very handsome color in connec- 
tion with rubber, but is rarely used, as it is not permanent if other 
metals, such as copper, brass, iron, and zinc, come in contact 
with it. 

Crimson Sulphide of Antimony. — This is altogether the 
best antimony color now in use. It not only gives a fine shade of 
orange or red, but it also is an excellent vulcanizing agent. 

Colcothar. — A form of oxide of iron of the specific gravity 
of 4.8 to 5.3. It is the residue left in the manufacture of fuming 
sulphuric acid from green vitriol. The least calcined portions, 
which are scarlet in color, are termed jewelers' rouge, and the 
more calcined parts, of a bluish shade, are called crocus. Its 
composition is that of ferric oxide. In its reaction it is indifferent, 
being very stable under ordinary conditions. Colcothar is a dull 
red and is often used in red packings, soleings, etc. Many rubber 



YELLOWS. 185 

chemists prepare their own Colcothar, as they are able to get 
brighter shades than is possible from the goods ordinarily sold in 
the open market. 

Umber. — A brown earthy mineral, containing chiefly the 
oxides of iron and manganese. The following analysis, by Pro- 
fessor A. H. Church, is taken from a choice specimen of Cyprus 
Umber: Oxide of iron, 48; oxide of manganese, 14; silica, 13.7; 
water yielded at a heat of 212° F., 4,8; mixture of lime, mag- 
nesia, alumina with organic matter, 14.5. In using Umber for 
rubber compounding, care should be taken to dry the material 
thoroughly at 212° F., before it is used. Burnt Umber is the 
product obtained by roasting the above material. It is slightly 
redder in color and will. naturally contain less water. For brown 
colors, in addition to Umber, various natural earthy matters are 
used, as are also oxysulphide of antimony and sepia, the latter 
being an animal coloring matter made from the bright fluid 
formed in the ink bag of cuttle fishes. Sienna and chestnut 
brown are practically the same as Umber, while Vandyke brown 
is made of oxide of iron, ground very fine, and is not injurious 
to rubber. While these ingredients are practically inert, they do 
not make the best of rubber compounds, as the resulting com- 
pound is apt to have a hard stony feeling. 

Prussian Red is an oxide of iron prepared from copperas, 
and, therefore, it is the same as the modern rouge or oxide of 
iron. 

YELLOW. 

Yellows are not often demanded in rubber work, except in 
a few fancy articles and in hose markings. The most common 
is that produced by the golden sulphuret of antimony, but color 
is not what is sought in the use of that ingredient, but rather the 
excellent rubber produced by it when used instead of sulphur. 
Other mineral yellows used are strontium, chromium, cadmium, 
barium, and arsenic. Chrome yellow is made from a lead base 
which darkens when subjected to vulcanization. 

Cadmium Yellow. — This is the best pigment for producing 
yellow in a rubber compound. It does not injure the elasticity 
or strength of the India-rubber in any way, and, while it has no» 



i86 COLORING MATTERS AND PROCESSES. 

special effect on vulcanization, perhaps hurries it a little. It is 
not injurious to the health of persons using it, and is generally 
used for surface ornamentation of toys, etc. It is sometimes 
mixed with yellow sulphide of tin to cheapen it. While Cadmium 
was ruled against in the German anti-poison act, the sulphides of 
this metal were made an exception, and said to be safe. In dental 
plates, however, where the coloring matter was used in large 
quantity, it was advised against. The costliness of Cadmium 
Yellow at present bars its general use in rubber. 

AuREOLiN Yellow. — A very handsome color, and one that 
is stable and brilliant. It is made up of acetate of cobalt and 
nitrate of potassium. The color stands the light well, and sul- 
phur compounds have little influence upon it. This is chiefly used 
for surface work. 

: Gamboge Yellow. — Obtained from the Garicinia morella. 
It contains from 20 to 25 per cent, of gum, 65 per cent, of resin. 
3 per cent, of volatile oil. It is soluble particularly in spirits, in 
a number of oily liquids, and partially in water. Finely pulver- 
ized Gamboge may be mixed with rubber, and is said to be a 
preservative of it. 

. Barberry Yellow. — Made from the root or bark of the 
Barberis vulgaris. It is largely used in coloring leather surfaces, 
and, in connection with gamboge, is said to be useful in rubber 
work. 

Yellow Ocher. — There are several ocbers, all of them 
being practically oxides of iron mixed with clay. They are earthy 
substances of no particular reaction, very stable, having a specific 
gravity of about 5. Their low cost renders them available for 
altnost any work, but the colors produced are not especially 
beautiful. 

■ Arsenic Yellow. — Also known as King's Yellow, and is a 
term applied to sulphide of arsenic. A cheap grade of this, which 
is really only an imitation, is manufactured by mixing together 
litharge and white arsenic, and grinding the product. Either of 
these, of course, is poisonous, and they are very rarely used or 
needed in connection with rubber. The specific gravity of Arse- 
nic Yellow is 3.48. Although a sulphide, there is not enough 
sulphur in its composition to vulcanize India-rubber. On account 



GREENS. 187 

of its poisonous properties, this yellow has been largely super- 
seded commercially by the comparatively harmless chrome yel- 
lows. Another name for this color is orpiment. It was often 
used in rubber compounds of twenty years ago. A small quantity 
in white zinc stock takes off the glaring white effect, and pro- 
duces a handsome cream white. Must be in an impalpable pow- 
der to bring out the color. 

' Chrome Yellow. — Ordinarily the chomate of lead, which 
is largely used as a pigment. It is somewhat poisonous and is 
apt to oxidize organic substances, particularly if sulphur be pres- 
ent. Has been used in the surface ornamentation of rubber toys, 
but such use is generally condemned. The only Chrome Yellows 
that are really valuable for rubber work are the chromate of zinc, 
or possibly the chromate of strontium. 

Orpiment. — See Arsenic Yellow. 

Dutch Pink is the name given to some common yellow 
lake pigments made from Persian berries, quercitron bark, fustic, 
etc., on a base of China clay or whiting. It is mentioned here 
just to notice that at one time a blue Dutch pink was known, 
prepared from the woad plant. 

GREEN. 

It is fortunate that greens are not largely sought in the rub- 
ber industry, for they are rare. Arsenic greens in many cases 
are not to be thought of ; therefore, about the only ones that are 
available, unless very high cost goods can be utilized, are the 
following : 

Chrome Green. — A coloring matter that is not affected by 
strong acids, or alkalies, and which is inert when mixed with 
India-rubber. It is the best mineral green that can be used in 
connection with rubber. It is really a sesquioxide of chromium; 
and may be mixed with rubber, with any kind of solvent, and 
with other oxides and pigments, without hurt to the compounds. 

Terra-verte is of mineral origin, and is imported in large 
quantities from Italy. It is a pale neutral green of moderate cost, 
and is not injurious to rubber. On analysis it shows, as in the 
following table, the analysts quoted being Klaproth for No. i and 
Bcrthier for No. 2: 



i88 COLORING MATTERS AND PROCESSES. 

No. I No. 2 

Silica 51.50 46.00 

Alumina 12.00 11.70 

Protoxide of iron 17.00 1740 

Lime 2.50 3.00 

Magnesia 3.50 8.00 

Soda 4.50 

Water 9.00 13.90 

Total loo.o loo.o 

Green Ultramarine is made by a process very similar to 

that made in producing blue of that name, and its action upon 

rubber is almost identical with that of ultramarine blues. 

Hungarian Green is a similar pigment found at Kem- 

hausen in Hungary, These greens in some respects resemble the 

article now. known as terra- verte. 

Saxon Green is a green earth of a clayey nature, found in 

parts of Saxony. 



CHAPTER X. 

ACIDS, ALKALIES, AND THEIR DERIVATIVES, USED IN THE RUBBER 
MANUFACTURE. 

As a rule neither acids nor alkalies, in the strict sense of the 
term, are largely used in ordinary rubber compounding. In a 
great many of the processes, however, that go far to make up 
finished goods, acids are used, as, for example, in those employed 
in the reclaiming of rubber chemically. Alkalies also are most 
necessary, a notable example being the use of caustic potash and 
caustic soda solutions in removing sulphur from manufactured 
goods. A great variety of uses other than these may be indicated. 

Acetic Acid. — This is usually obtained by the dry distilla- 
tion of wood fiber, peat, or sawdust. The strongest form is 
known as glacial and occurs in large watery crystals, readily 
liquefied. The common commercial acid usually has a brown or 
yellowish color, due to impurity, since the pure acid is colorless. 
Its specific gravity is 1.05, and it has a characteristic odor familiar 
enough in vinegar. As an acid it is not very corrosive, and its 
compounds are easily decomposed by mineral acids. It is quite 
volatile. The primary use of this acid in connection with India- 
rubber is in the coagulation of rubber milk. It is a prominent 
component part of the smoke used in coagulating fine Para rub- 
ber. It has also been used under the Vaughn process for coagu- 
lating Balata, and in the manufacture of certain substitutes like 
linoxin, Parkesine, etc. ; in connection with nitro-cellulose and 
castor oil in the production of certain waterproofing compositions ; 
by Brooman in separating whiting, white lead oxides, etc., from 
vulcanized rubber; and in shoemakers' blackings in connection 
with caoutchouc oil, vinegar, molasses, and lampblack. 

Ale. — A beer made from malt, distinguished chiefly by its 
strength and the quantity of sugar remaining undecomposed, 
which enables the liquor to keep, without requiring a large amount 
of hops. A mixture of ale and linseed oil, in the proportions of 
8 parts ale to 2 parts linseed oil, is used in dissolving isinglass, 

189 



I90 ACIDS AND ALKALIES. 

in which are afterward incorporated shellac and India-rubber in 
the formation of what is known as ale cement. 

Alum. — A general term for several chemical compounds of 
aluminum, potassium, chromium, and ammonium. Common alum 
is the double sulphate of potassium and aluminum, having a 
specific gravity of 1.7 and containing 45 per cent, of water of 
crystallization, one-quarter of which is expelled on heating to 140° 
F. It is soluble in water 9^ parts per 100 when cold, 357 parts per 
100 when hot. Chrome Alum is a double sulphate of chromium 
and potassium, its specific gravity being 2.7, and containing 43 per 
cent, water of crystallization, which is almost entirely lost at 392'' 
F. It occurs as dull purple crystals, slowly soluble in water to 20 
per cent, in the cold and 50 per cent, in the hot water. Its action 
on gelatine is remarkable for its hardening qualities. Ammonia 
Alum, the double sulphate of aluminum and ammonia, is largely 
used in place of common alum. It contains 48 per cent, of water 
of crystallization and has a specific gravity of 1.63. Strongly 
heated, it yields sulphate of ammonia, water and a very small 
quantity of sulphuric acid, while alumina is left behind. It is 
soluble in water 13 per cent, cold, 422 per cent. hot. Roman 
Alum has the same general characteristics as common alum, but 
contains a little more alumina. 

Alum is used in many of the shower-proof mixtures for cloths 
of the cravenette order, that are to-day bought and made up by 
manufacturers of mackintoshes. It is also sometimes used in the 
manufacture of sponge rubber. By Gamier's process it is also 
used in spirituous solution to cure rubber without heat by mixing 
with it. Used also in Wray's substitute for Gutta-percha. Alum 
was used in Payne's Gutta-percha compounds for proofing, var- 
nishing, and paints. Ghislin, who prepared some curious com- 
pounds from seaweed and India-rubber, mixed alum, gelatine, 
and metallic oxides in his compounds. It is also sometimes used 
in compounding rubber to make sponge effects, and mixed with 
sulphate of iron and soap, in a water mixture with boiled linseed 
oil, to make flexible waterproofing compounds. 

Ammonia^ at ordinary temperature, is a colorless gas of well 
known odor and sharp biting taste. It is usually met with in the 
arts in watery solution, the specific gravity of which varies with 



AMMONIA— BARIUM CHLORIDE. 191 

the amount of ammonia gas dissolved. The strongest, sometimes 
called caustic ammonia, contains 32.5 per cent, of the gas, and 
has a specific gravity of .875. Ordinary commercial ammonia 
has a percentage of 9.5 and a specific gravity of 0.96. The weak- 
est usually has a percentage of 5.5 and a specific gravity of .978. 
Ammonia has a powerful solvent action upon sulphur, is alkaUne 
in its nature, and very volatile, so that much care is requisite in 
handling it. It has long been known to have a preservative effect 
upon India-rubber; for example, low grade African rubbers are 
often treated with Ammonia to neutralize the smell, and also to 
toughen the rubber. In the cold-curing process a saucer of Am- 
monia put in the bottom of the vapor room will effectually neu- 
tralize the fumes of chloride of sulphur. It is also advised to 
wash vulcanite that has begun to perish with an Ammonia solu- 
tion. Soft rubber goods also are preserved, according to Dr. 
Pol, by the immersion for an hour in a solution made of i part of 
ammonia and 2 parts of water. 

Sievier dissolved India-rubber in Ammonia, leaving it in a 
closed vessel for a long time, after which he heated the solution 
and distilled the Ammonia gas in cold water. Concentrated liquor 
of Ammonia is added to milk of the rubber tree to preserve it for 
transportation. Where vegetable fibers are reduced to cellulose 
and mixed with India-rubber, the rubber is first steeped in Am- 
monia and then dissolved in some suitable solvent. Newton mixed 
Ammonia with India-rubber and Gutta-percha, and then treated 
the gum with chlorine, making a white hard compound which 
he claimed would stand all varieties of climates, acids, greases, etc. 

Aniline. — A colorless oily liquid, manufactured chiefly from 
coal tar or nitrobenzine. It is a base from which the brilliant 
aniline dyes are made. Aniline, used by Parkes in the manufac- 
ture of Parkesine, is also a solvent for Gutta-percha. 

Arsenate of Potash. — It is a very soluble compound of 
arsenic with potash and forms what is known as Fowler's solu- 
tion. In the dry state it is a white powder soluble in alcohol up 
to 4 per cent. Arsenate of Potash was used by Forster, among 
his earliest experiments, to partially vulcanize a compound made 
up of India-rubber and shellac. 

Barium Chloride. — A white crystalline powder, insoluble in 



192 ACIDS AND ALKALIES. 

alcohol, but soluble in hot water, 78 per cent., and in cold 38 per 
cent. Its specific gravity is 3.05. It is not of great technical im- 
portance, its principal value being that of a test for sulphuric acid. 
To makers and users of sulphurets it affords a ready means of 
determining the presence of free sulphuric acid, so liable to occur 
in these bodies and so injurious to rubber compounds when pres- 
ent. A suspected sulphuret should be boiled for a moment with 
a little distilled water, the water filtered off, and a drop or two 
of a solution of Barium Chloride added ; a white cloudiness that 
will settle in the form of a white powder proves the presence of 
sulphuric acid and such a sample should be rejected. Barium 
Chloride is a powerful poison. Used with size and acid resin as a 
shower-proof mixture. 

BisuLPHATE OF PoTASH. — A white powder obtained as a by- 
product in chemical manufacturing. Soluble in twice its weight 
of cold water, and in half its weight of boiling water. It contains 
sulphuric acid so loosely held in combination that it is driven off 
upon heating. Its specific gravity is 2.16. (See Potash.) 

Bichromate of Potash. — The principal compound of chro- 
mium, which occurs in the form of orange red crystals, that are 
soluble in water and are largely used in dyeing. Mixed with sul- 
phuric acid, it is used in bleaching palm oil and other fats. Bi- 
chromate of Potash is used in vulcanizing the compound known 
as elastic glue ; also used in Christia gums. 

Bleaching Powder. — See Chloride of Lime. 

BoRACic Acid. — This is found native in the vapor which 
arises from certain volcanic rocks, in a saline incrustation in vol- 
canic craters and in combination with borax. It appears in the 
form of pure white leathery crystals. Boracic Acid is used with 
tungstate of ammonia, kauri, borax, and India-rubber in the pro- 
duction of the woodite fireproof compositions. 

Borax or Biborate of Soda. — Sometimes also called Tincal ; 
a compound of soda and boracic acid. The purified commercial 
article contains about 47 per cent, of water of crystallization and is 
usually in the form of large odorless crystals, or a white powder 
obtained by grinding. The crystalline form has a specific gravity 
of 1.69. Borax is quite soluble in water, but not in alcohol or 
any of the common solvents for rubber. At a moderate heat 



BORAX— CARBOLIC ACID. 193 

Borax loses water, and separates as a spongy mass called cal- 
cined borax, while at a higher heat it melts into what is known as 
borax glass. Immense deposits of it are found in the United 
States, and it is also found in India, Hungary, and other parts 
of the world. A good waterproof cement is made of a mixture of 
Borax and shellac boiled in water. Borax, or a solution of biborate 
of sodium, has the property of dissolving many resins. Lascelles- 
Scott describes the manner in which an emulsion of rubber may 
be preserved by a Borax solution. To a solution of rubber, in 
any one of the common solvents, a small portion of alcohol is 
added. This is mixed with a 2-5th saturated solution of Borax, 
previously heated from 120° to 140° F. This is agitated until the 
temperature has cooled down to the temperature of the air. From 
3^ per cent, to 4I per cent, of India-rubber should be present 
in the fluid when finished. A higher strength quickly separates 
and sometimes causes the entire quantity to coagulate. Madagas- 
car or Sierra Leone rubbers are advised for Borax solutions. 
Solutions of borated rubber are adapted for waterproofing and 
for preserving mats, marine bedding, etc. Borax is also advised 
for preserving rubber milk from coagulation. It is also an im- 
portant ingredient in the water varnishes used for luster finish, 
for surface coats, army blankets, etc.; is used in waterproofing 
compounds composed of rubber, boracic acid, kauri, tungstate 
of ammonia ; mixed with Gutta-percha and shellac, it w^as used by 
Hancock as an insulating material. 

Carbolic Acid, also known as Phenic Acid, is obtained 
chiefly during the destructive distillation of coal. The liquid 
has a hot burning taste, and is largely used for its antiseptic 
qualities. If white crystallized carbolic acid be added to the paste 
from which matrices in rubber stamp making are manufactured, 
it preserves the mixture for a long time. Carbolic Acid is used as 
a preservative of rubber milk, where it is coagulated by the pro- 
cess some time employed by the Orinoco Co., in Venezuela. Car- 
bolic Acid has also been used in connection with a little ammonia 
to increase the elasticity of low grade African gums, being used 
as a solution before the gums are washed. It is also used for 
treating fabrics, such as hose linings for fire and mill hose, to 



194 ACIDS AND ALKALIES. 

prevent deterioration and rotting. Used in certain fiber-made 
substitutes. 

Carbonate of Ammonia, obtained during the dry distilla- 
tion of bones, is a white crystalhne powder of very penetrating 
smell, from which quality it takes its popular name of smelling 
salts. Exposed to the air, it yields ammonia and absorbs water, 
becoming superficially converted into bicarbonate. It is used 
industrially for the removal of grease from cloth and cleaning 
woolen fabrics. Carbonate of Ammonia is used also in the manu- 
facture of sponge rubber, and in hollow work, where its expan- 
sive force is utilized to efifectually mold the article. 

Carbonate of Soda. — Also called Sal-soda, washing soda. 
Prepared from cryolite, salt, etc. Its specific gravity is 1.45, when 
crystallized. The crystalline form contains 64 per cent, of water 
of crystallization, of which one-half is driven ofiF by gentle heat- 
ing. It is a white crystalline substance of alkaline taste. It is 
found in the ashes of many plants, is produced artificially in 
large quantities from common salt, and is used as an alkaline 
agent in many chemical industries. India-rubber, burnt umber, 
Japan, and a coloring matter are mixed with a certain proportion 
of Salsoda for a waterproofing composition. Under the cc«nmon 
name saleratus. Carbonate of Soda is used as follows: Instead 
of sunning surface goods, like rubber coats and blankets, they are 
often brushed over with a mixture of saleratus and powdered 
charcoal right after the stock leaves the calender. Sometimes the 
saleratus is left out and only charcoal is used. 

Caustic Soda. — The chief use of this, in the manufacture of 
rubber goods, is in the dissolving of sulphur that is formed on 
the surface of goods, and which is known as bloom. According 
to H. L. Terry, F.I.C., the bulk of the alkali supplied to rubber 
manufacturers in England is used in removing the sulphur from 
elastic thread. Of course it is used in treating tobacco pouches, 
fine sheet articles, and blacks, reds, or maroons, that should have 
a good clear color. The boiling of rubber goods is usually done 
in wooden tanks in which steam can be passed, and sometimes in 
slate tanks, as iron is attacked by the alkali. On good grades of 
rubber caustic soda has no action at all ; where a large quantity of 
resin is present, however, it may dissolve some of them, forming 



CATECHU^CAUSTIC POTASH. 195 

resinates of soda. Heavily compounded rubbers, whether they 
contain substitutes, gums, or compounds, unless they are abso- 
lutely inert, are also liable to be attacked through the dissolution 
of their ingredients. Camille describes a process whereby shoddy 
is treated with a solution of carbonate of soda in devulcanization. 
In this, the rubber is boiled several hours in a solution of caustic 
soda, the result being that it will sheet when the process is com- 
pleted. Rostaing purified Gutta-percha, by boiling in caustic 
soda, or in a mixture of caustic soda and potash in water. 

Catechu, or Cutch. — Known formerly as Japan Earth. 
Made from the sap of an East Indian tree, and used chiefly in 
dyeing. Is very astringent, and is soluble in water. It appears 
in commerce in dark brown irregular lumps. Contains 40 to 50 
per cent, of a peculiar tannic acid. Used in packings and goods 
made from the whaleite formulas. Johnson's artificial leather was 
made of Catechu, rosin oil, linseed oil, turpentine, and starch, 
mixed with a little hot Gutta-percha. A number of other com- 
pounds, both with and without India-rubber, contain Catechu, 
but chiefly those which were compounded from gelatine, starch, 
and gluten. Catechu is mixed with Gutta-percha in solution in 
order to make it harder. 

Caustic Ammonia. — See Ammonia. 

Caustic Potash. — As occurring in commerce, it is a white 
solid substance of the specific gravity about 2.5. It is hard and 
brittle, and very destructive to animal or vegetable substances. 
It rapidly takes up water from the air, and may be used to obtain 
a dry atmosphere in a confined vessel. It is also a greedy absorb- 
ent of carbonic acid, becoming converted into the carbonate 
thereby. Solutions of potash should be clarified by allowing im- 
purities to subside. Its taste is bitter and acid and its smell un- 
pleasant. Alcoholic Caustic Potash is used in analysis of vul- 
canized India-rubber and was introduced by Henrichs, particu- 
larly to separate India-rubber from India-rubber substitute. 
Caustic Potash is mixed with flowers of sulphur for boiling draw- 
ing rolls, the potash making the rubber more solid, while the sul- 
phur gives a peculiar surface, making it better for drawing. Used 
in water solution to remove bloom from cured rubber. It is also 
used in certain substitutes for hard rubber, like voltit. PotaSh 



196 ACIDS AND ALKALIES. 

was early used in extracting the sulphur from ground vulcanized 
rubber. A percentage of it is used to-day in neutralizing the acid 
used in the chemical recovery of rubber. 

Chloride of Ammonium. — Also known as Muriate or Hy- 
drochlorate of Ammonia, or Sal-ammoniac. Obtained largely 
from gas works. Specific gravity 1.5. Usually occurs in small 
crystals of a sharp, saline taste. When dissolving in water a con- 
siderable reduction of temperature occurs, and this has rendered it 
valuable for cooling purposes. At temperatures above 212° F. 
it is completely evaporated, and a decomposition occurs into am- 
monia and muriatic acid. It is used in certain packings in which 
iron filings are incorporated. 

Chloride of Calcium. — A crystalline substance containing 
about 50 per cent, of water of crystallization, which is lost on 
heating to 392° F. The specific gravity is 1.61, and that of the 
dried form 2.21. Its extreme attraction for water makes it use- 
ful in obtaining a dry atmosphere in any closed receptacle. Its 
color is white, taste acid and sharp. It absorbs ammonia readily 
and will give it up again on heating. It is used in bookbinders' 
cements. 

Chloride of Lime. — Sometimes called bleaching powder, 
although this latter is a mixture of the chloride and hypochlorite 
of lime. Industrially, its chief use is for bleaching purposes, de- 
pendent upon the amount of chlorine it contains. Commercial 
bleaching powder is a white powder with a faint smell of peculiar 
character and gradually becoming moist on exposure to the air, 
while it gradually decomposes and absorbs water and carbonic 
acid. Even in closed vessels decomposition occurs, and some- 
times so suddenly and with such a rise of temperature that explo- 
sions occur. Hence it should always be used fresh and a guaran- 
tee obtained from the vendors (as is customary) of the quality of 
the article. Chloride of Lime is the basis of a cold curing proc- 
ess known as Caulbry's (which see). Gutta-percha boiled in it 
and then mixed with rosin and paraffine is used in insulation. 

Chloride of Sodium (or common salt) has a specific grav- 
ity of 2.3. It is a very stable compound, soluble in water at the 
ordinary temperature to the extent of 36 per cent., at the boiling 
point 39 per cent. At the freezing point water will take up 554 



CHLORIDE OF ZINC— CREAM OF TARTAR. 197 

per cent, of common salt. It is used, as is well known, in coagu- 
lating many of the rubber latexes. Salt is viewed with considerable 
distrust by ordinary manipulators of rubber. Payne, however, 
treated Gutta-percha scraps by boiling water, salt, and oil of vit- 
riol, to get a solution to which he added other gums and metallic 
oxides to get a waterproofing mixture. Cooley made artificial 
leather of Gutta-percha dissolved in rosin oil, and added 25 per 
cent, or more of salt, to which he added starch or other saccha- 
rine substances. Salt, in the form of brine, is used in washing the 
compound known as tremenol as a last process. It is also used in 
shower-proofing compounds, in connection with paraffine and sul- 
phuric acid. 

Chloride of Zinc was known formerly as Butter of Zinc. It 
is formed by burning zinc in chlorine gas, or by dissolving it in 
hydrochloric acid, the solutioin being evaporated. The anhydrous 
form is a whitish gray mass which readily fuses, and can be sub- 
limed at a high temperature. It deliquesces on exposure to the 
air, and is readily soluble in water, the solution having a bitter 
taste, and acting in a concentrated state as a powerful caustic. 
One of the best processes ever known for reducing the fiber in 
recovering rubber was that in which this substance was employed 
instead of acid. A boiling solution of Chloride of Zinc was used 
in deodorizing by Brockedon, who also mixed it with Gutta- 
percha, adding sulphur and vulcanizing the gum. Hancock also 
subjected Gutta-percha for a moment or two to binoxide of nitro- 
gen, then immersing it in a boiling solution of chloride of zinc, 
which he claimed greatly improved its quality. 

Chromic Acid is not readily obtained in a free state, but 
forms many well-known salts, such as chrome yellow, for in- 
stance. It is analogous with sulphuric acid. Vulcanized rubber 
immersed in it at 140° F. remained a month, and was apparently 
unharmed. It is also used in the manufacture of the substitute 
known as corkaline. 

Citric Acid. — An organic acid that occurs in lemons, 
limes, and many other fruits. It is readily soluble in water, and 
has an intensely sour taste. Has been used in the coagulation 
of Balata. Vulcanized rubber immersed in it at 140° F. re- 
mained a month, and was apparently unharmed. 



198 ACIDS AND ALKALIES. 

Cream of Tartar. — A white crystalline substance with an 
acrid taste, a very common ingredient in baking powders; also 
called Potassium Bitartrate. It is made from purified tartar, or 
argol. It is used in artificial ivory made from resins in solution. 

Crystals of Soda. — See Carbonate of Soda. 

Cyanide of Potassium. — A white crystalline substance, very 
poisonous, of a sharp bitter taste. It is very easily decomposed, 
even on exposure to the air absorbing carbonic acid and yielding 
prussic acid, which gives the salt its peculiar smell of peach ker- 
nels. The vapors thus given off are very poisonous. Cyanide of 
Potassium was used by Brooman "to give clearness to the gum 
which was made from ground vulcanized rubber, which had been 
treated with alkalies and acids to remove sulphur and adulterants." 

Fluoride of Silicon is a colorless gas. What is used in the 
arts is a solution in water, forming a very sour fuming liquid, 
acting like a strong acid. It is easily decomposed and may be 
used for etching glass if allowed to evaporate upon it under heat. 
It is prepared from flints or silica in some such form as sand or 
powdered glass. Used in treating meerschaum and paper pulp 
which, combined with certain resins, forms an artificial ivory. 

Formic Acid obtains its name from the fact that it was first 
obtained from the red ant. It is a fuming liquid with a pungent 
odor, boiling at 212° F. It is now made from a mixture of 
starch, binoxide of manganese, sulphuric acid, and water. It has 
been suggested as an ideal precipitant for rubber milk. It is 
quite volatile, could be easily washed out, and would be found 
more beneficial to the rubber than many of the alkaline solutions 
now used, 

Hydrochlorate of Ammonia. — Another name for Muriate 
of Ammonia or Sal-ammoniac. (See Chloride of Ammonium.) 

Hypochlorite of Lime. — One of the principal constituents 
of bleaching powder. It does not exist alone. ( See Chloride of 
Lime.) 

Hydrosulphuret of Lime. — Lime that has been treated 
with hydrogen sulphide. It is an offensive smelling substance, 
of a dirty greenish gray appearance, and is obtained in the process 
of purifying coal gas. It decomposes easily, giving off sulphu- 
reted hydrogen. It will absorb bisulphide of carbon and is solu- 



HYDROCHLORIC ACID— IODIDE OF ZINC. 199 

ble in alcohol. Its liability to oxidize should render it of ques- 
tionable use in compounding. It was used by Hancock in vulcan- 
izing India-rubber. 

Hydrochloric Acid is known usually by its trade name of 
Muriatic Acid. It is also known as chlorhydric acid, and spirits 
of salt. It is one of the principal mineral acids. Used in the arts 
in the form of a water solution, of which the strength varies 
from a specific gravity of i.oi or 2° Beaume with 2.02 per cent, 
acid to 1. 21 or 26° Beaume, with 42.85 per cent. acid. Each .01 
increase of gravity corresponds to 1° Beaume and 2.02 per cent, 
of acid. It is corrosive to the skin and attacks nearly all 
metals. It has no action on caoutchouc and very little on oxidized 
linseed oil if the acid be dilute. With soda and its compounds 
generally speaking it will form common salt and with metals it 
forms chlorides thereof. Hydrochloric Acid, during the treatment 
of reclaimed rubber, turns whiting into chloride of lime. As the 
chloride is more soluble than sulphate of lime much of it washes 
out during the vigorous cleansing that the rubber undergoes to 
remove the free acid. Hydrochloric Acid, according to tests made 
by William Thompson, F.R.S., did not at all injure India-rub- 
ber, although it was kept in it at a temperature of 140° F. for a 
month. Concentrated Hydrochloric Acid has but little action on 
Gutta-percha, and tubing made from it is therefore largely used in 
chemical factories for running this acid from one vessel to an- 
other. Hydrochloric Acid is used in the manufacture of turpen- 
tine rubber, and in one of the last processes in the analysis of 
vulcanized India-rubber. In preparing a hard rubber compound, 
Austin G. Day used linseed, cottonseed, castor, and coal oils ; hy- 
drochloric and nitric acids; bicarbonate of soda, muriate of tin, 
coal tar asphaltum, sulphur, and Gutta-percha. 

Iodide of Antimony. — A brownish red crystalline mass, 
which yields a cinnabar red powder. It is soluble in hot carbon 
bisulphide. Its specific gravity is 4.39. It was used by Parkes 
in vulcanizing India-rubber. 

Iodide of Zinc. — A very unstable substance. A white gran- 
ular powder, odorless and of sharp, saline metallic taste. Chiefly 
used in medicine. It was used by Hancock to assist in the vul- 
canization of India-rubber. 



200 ACIDS AND ALKALIES. 

Liquor of Flint. — See Silicate of Soda. 

MiMO-TANNic Acid. — See Catechu. 

Muriate of Ammonia. — See Chloride of Ammonium. 

Muriatic Acid. — See Hydrochloric Acid. 

Nitrate of Lead. — A compound of lead and nitric acid con- 
taining 62.5 per cent, of lead. Its specific gravity is 4.58. It has 
an astringent metallic taste, crackles when heated, detonates when 
thrown on red hot charcoal, and takes fire when ground with sul- 
phur. Its color is white and it is largely used in dyeing and for 
making chrome yellow (which see). It is used with gums in the 
production of shower-proof mixtures with sugar of lead and 
alum. 

Nitric Acid. — Chemically an oxide of nitrogen. Technically 
a strongly acid liquid consisting of an aqueous solution of the pure 
acid. Its action on different bodies is various. Some, like sul- 
phur, phosphorus, carbon, and many organic substances are easily 
oxidized. Tin and powdered antimony are rapidly converted into 
their oxides, while turpentine, if poured into the strong acid, is 
attacked with almost explosive violence with the evolution of light 
and heat. Straw or sawdust may become ignited if impregnated 
with this acid. Cotton wool is converted by it into gun cotton. 
Rubber immersed in Nitric Acid at a temperature of 140° F. was 
injured in a few hours, and in a few days its elasticity was de- 
stroyed, while at the end of the month it was reduced to a pulp. 
Nitric Acid attacks Gutta-percha very powerfully, and evolves 
suffocating fumes of a deep red color, the gum meanwhile being 
reduced to a pasty mass which afterwards dries and becomes very 
brittle. According to H. L. Terry, F.I.C., Nitric Acid of any 
strength has a very deleterious effect upon India-rubber, the action 
of the fuming acid being to form immediately an oxidized body of 
a resinous nature. He holds, therefore, that the weaker acid also 
injures the India-rubber, although of course in a less degree. 
Nitric Acid is used in the treatment of leather cuttings to reduce 
them to a glutinous mass before being mixed with India-rubber, 
and is also used in making certain substitutes. 

Nut-Gall. — An excrescence formed on the leaves of a spe- 
cies of oak called Quercus infectonia. It is used in the arts for the 
sake of the tannic acid it contains. There are three varieties in 



OLEIC ACID— PEROXIDE OF HYDROGEN. 201 

commerce — green, white and black. The black and the green are 
the best. Those grown in warm countries are the best. Aleppo 
galls contain from 60 to 66 per cent, of tannic acid. There is a 
variety of nut-gall known as Chinese, imported from Japan, 
China, and Napal. The gall is somewhat bean-shaped or is cov- 
ered with a yellow gray felt. It contains from 60 to 70 per cent, 
of tannic acid. Nut-gall is used in certain places instead of tan- 
nin, which see. 

Oil of Vitriol. — See Sulphuric Acid. 

Oleic Acid. — An acid found in certain animal and vegeta- 
ble oils, such as olive oil, sperm oil, etc. It has been used in cer- 
tain substitutes for hard rubber, like voltit, and by Hunt for re- 
covering waste vulcanized rubber under heat, methylated spirit 
being added later to precipitate the rubber, which was then 
washed in a weak caustic soda. 

Oxalate of Lime. — Quick lime slaked by water in which is 
oxalic acid is given this name. Used in certain Gutta-percha 
compounds. 

Oxalic Acid occurs in transparent, colorless prisms, with a 
very sour taste, soluble in both cold and hot water. It is pro- 
duced by either the action of the hydrate of potash, or of nitric 
acid upon most organic compounds. It is very poisonous. Gutta- 
percha was cleansed by Lorimer's process by boiling in water 
mixed with this acid. 

Permanganate of Potash occurs in dark red prisms of a 
greenish color which, when dissolved in water, give a purple red. 
It is a decided oxidizer, and is used as a disinfectant. It is also 
called chameleon mineral. Used in certain artificial leathers. 

Peroxide of Hydrogen. — This is a powerful oxidizing 
agent, largely used as a bleaching agent, and also as an antichlor 
for use after chlorine bleaching. It comes in the form of a color- 
less liquid, and has a specific gravity of 1.45. Neither the alka- 
line nor the acid solutions of this reagent seems to impair vul- 
canized India-rubber. In certain cases Peroxide of Hydrogen 
has been used in removing the bloom from rubber, which it does 
most effectively ; besides, it seems to penetrate the surface of the 
rubber and dissolve the sulphur. It also has a curious effect on 
colors, brightening some reds wonderfully, dulling others, and 



202 ACIDS AND ALKALIES. 

rendering whites much whiter. One curious effect that it has 
upon India-rubber is to bring out any surface imperfections in a 
marked degree. 

Phosphate of Soda. — A crystalHne colorless substance con- 
taining 60 per cent, of water, which is given up on heating to 
248° F., leaving behind a dry mass. The commercial article fre- 
quently contains sulphate of soda as an impurity. The crystals 
have a specific gravity of 1.5, melt at 95° F., and are readily soluble 
in water. By long drying at 113° F. the water of crystalliza- 
tion may be entirely driven off. The presence of this material 
is called for in a certain compound for dental vulcanite, where it 
is incorporated with rubber, sulphur, and phosphate of lime, the 
idea being that less sulphur is required than in the ordinary com- 
pounds. 

Phosphoric Acid. — See Phosphorus, 

Potash. — This substance, a carbonate of potassium, is 
usually met with commercially in small colorless crystals. It- is 
prepared in a variety of ways and forms, the basis from which is 
prepared what is called caustic potash. Pearl ash is a crude form 
of potash mixed with the caustic variety and a sulphuret of potas- 
sium. Used in certain proofing compounds where low heat is 
required for cure. It was used by Charles Hancock, mixed with 
water in a bath, to improve the quality of Gutta-percha. He 
found, by boiling the Gutta-percha in such a bath for an hour, 
that it did not oxidize in the open air as badly. An old-fashioned 
process for treating unvulcanized thread was to steep it in a hot 
solution of carbonate of potash, which greatly increased its 
strength. (See Caustic Potash.) 

Quick Lime is the impure oxide of calcium obtained by heat- 
ing or burning chalk, marble, or limestone, or any carbonate of 
calcium. Its well-known attraction for w^ater renders it unstable 
but also valuable where dyeing qualities are desired. Blizzard 
claimed to be able to make a perfectly transparent rubber by treat- 
ing it with soda and water, in which was a little Quick Lime. 

Reclaiming Salt. — An alkaline composition made in Ger- 
many and used chiefly in the reclaiming of red and light colored 
rubber waste. 

Rennet is made from the inner lining of the true stomach 



SALICYLIC ACID—SODIUM HYPOSULPHITE. 203 

of the sucking calf and gets its value from the gastric juice con- 
tained therein. The membrane, after treatment, is salted and 
stretched out to dry. It is advised in the Vaughn process for 
coagulating Balata. 

Salicylic Acid is obtained from the creeping plant known as 
wintergreen. It is prepared from the oil of wintergreen (oil of 
Gaultheria), which is distilled in large quantities in Luzerne 
county, Pennsylvania. It is soluble in the following proportions : 
I part of the acid dissolves in 450 of water, or 2.4 of alcohol. It 
melts at 312° to 314° F. Salicylic Acid was used in an artificial 
leather compound for reducing leather dust to a paste, after which 
it was mixed with glue under heat, and treated to an alkaline solu- 
tion. 

Sal Ammoniac. — See Chloride of Ammonium. 

Salt. — See Chloride of Sodium. 

Saltpeter is niter or potassium nitrate. It is a crystalline 
substance, white, and having a saline taste, and is a very strong 
oxidizer. It is used in the manufacture of artificial elaterite. In 
Gridley's process for recovering rubber, by exposing it to flame, 
saltpeter was added to remove the smell. 

Saleratus. — See Carbonate of Soda. 

Sal Soda. — See Carbonate of Soda. 
-Silicate of Soda. — See Soluble Glass. 

Soaps. — Various kinds of soaps are used in rubber manu- 
facture. Pure Castile soap, for instance, is dissolved in rain 
water and made into a soft soap that is used to "slick" molds that 
the rubber, during vulcanization, may not adhere to them. Some 
manufacturers use by preference white soda soap made from 
caustic soda and olive oil. Resin soaps are also used in certain 
shower-proof compounds. A further use for soap is in the manu- 
facture of water varnishes for luster coats and blankets. A soap 
compound for wagon covers is made of 50 pounds of soap dis- 
solved in 15 gallons of water, heated to 250° F., to which is 
added 25 pounds of sulphide of zinc. A half pint of rubber dis- 
solved in olive oil by heat is added to each gallon of the above 
mixture. Whiting, lampblack, or coloring matters may be added. 
Vulcanized rubber, beeswax, rosin oil, argillaceous earth, and 
alkaline soap form the basis of Sorel's substitute for rubber. 



204 ACIDS AND ALKALIES. 

Soda. — See Carbonate of Soda. 

Sodium Hyposulphite. — A i per cent, solution is used for 
removing traces of chlorine where its presence is suspected in 
India-rubber. 

Soluble Glass (known also as Waterglass) is a silicate of 
soda or potash. It is usually sold in solutions of varying density, 
the commonest being 33° and 66°, by which is meant that the 
solution contains either one-third or two-thirds solid waterglass. 
Acids readily precipitate the silica from these solutions as a 
gelatinous mass. It is used in certain shower-proof compounds 
and in compounds of the Algin (which see) type. 

Stearic Acid. — See Stearine, 

Sugar of Lead. — This is used in certain rainproof com- 
pounds, one of which is 16 parts of compounded rubber, 128 
parts of paraffine wax, i part of Sugar of Lead, i part of alum 
in powder. India-Rubber compound contains no sulphur. Used 
also in artificial rubber and artificial ivory. (See Acetate of 
Lead. ) 

Sulphate of Alumina. — The active principle of alum. 
Often sold as concentrated alum. Occurs commercially as white 
square cakes, somewhat transparent, and capable of being cut 
with a knife. Readily soluble in water, and contains a small 
quantity of free sulphuric acid, potassa, and soda alum. Its 
specifc gravity is about 4; water of crystallization 48 per cent. 
Its composition indicates a usefulness in compounding sponge rub- 
bers. Used in linseed oil compounds, for wagon covers. (See 
Alum.) 

Sulphate of Copper. — Sometimes called Blue or Cyprus 
Vitriol. Occurs in commerce in masses of large blue crystals 
having a specific gravity of 2.28, and containing 36 per cent, of 
water of crystallization, and a varying additional percentage of 
entangled moisture. Heated for some time at 212° F. all the 
entangled water may be driven off, together with four-fifths of 
the water of crystallization, the residue being a bluish white pow- 
der. Sulphate of Copper is used in attaching rubber to iron 
during vulcanization. 

Sulphate of Soda occurs commercially in colorless crystals 
which deteriorate in contact with the air, and hence should, be 



SULPHURIC ACID— TANNIN. 205 

kept in well closed vessels. It contains a vety large amount — 
nearly 60 per cent. — of water of crystallization, which is yielded 
on heating to 302° F. Its reaction is alkaline. Sulphate of Soda 
was used by Hancock in vulcanizing Gutta-percha. 

Sulphuric Acid (called also Oil of Vitriol), when pure, is 
a colorless oily looking heavy liquid of a sharp, sour taste. It is 
very corrosive, and has a great attraction for water ; hence wood 
and other organic bodies are charred by its depriving them of 
their water. The specific gravity of the commercial acid is 
usually about 1.83, or 66° Beaume, containing 94 per cent, of acid. 
Sulphuric Acid is used in the coagulation of Madagascar rubber. 
The Orinoco Co., in Venezuela, are also said to have coagulated 
India-rubber by mixing the milk of the Hevea with sulphuric 
and carbolic acid. Commercial Sulphuric Acid is said to coagu- 
late 55 times its volume of gum, while the carbolic acid acts as 
an antiseptic in the juice, improving its keeping qualities. It is 
a question whether rubber treated this way is as good as that 
obtained by the smoking process. Rubber immersed in Sulphuric 
Acid at 140° F. remained a month and came out stronger, 
apparently, than when it went in. Sulphuric Acid is used in paste 
blacking, mixed with boneblack, vinegar, molasses, and caout- 
chouc oil. Concentrated Sulphuric Acid colors Gutta-percha 
brown, throwing off at the same time sulphurous acid fumes. 
Nevertheless, a paste of this acid and charcoal was added by Han- 
cock to Gutta-percha to make it pliable. Sulphuric Acid may be 
expected to attack vulcanized rubber compounds in which there 
are large proportions of chalk, lead, or zinc oxides. Sulphuric 
Acid is very largely used in destroying the fiber found in ground 
waste rubber ; indeed it is the basis of what is known as the acid 
reclaiming process. When thus used the acid turns whiting into 
sulphate of lime. 

Tannic Acid. — See Tannin. 

Tannin includes a number of substances, some of which are 
crystalline and others amorphous, with a marked astringent taste, 
and no smell. The solutions are acid, soluble in water and alco- 
hol, and yield precipitates with most metallic oxides. It is the 
active principle of oak bark, hemlock bark, catechu, and many 
other materials usually used for tanning hides. Pure Tannin is 



2o6 ACIDS AND ALKALIES. 

a light powder of a yellow greenish hue, soluble in water, alcohol, 
and ether. Its solution precipitates glue. It is used with sul- 
phate of alumina, waterglass, and glue in shower-proofing. Tan- 
nin has been claimed to be injurious to rubber, the reason being 
that rubber thread used in gorings is often destroyed at points 
close to its junction with the leather. It is more likely, however, 
that it is the oil or oleic acid that effects the destruction. Tannin 
was largely employed by Austin G. Day in many of his "Kerite" 
compounds with excellent effect. It is also used in the manufac- 
ture of certain puncture fluids, together with glue and glycerine. 

Tartaric Acid is found usually in the form of transparent 
colorless prisms, which have an agreeable acid taste, are not 
affected by the action of the atmosphere, and are soluble in either 
alcohol or water. Nitric acid or peroxide of lead act upon Tar- 
taric Acid, turning it into formic and carbonic acid. This acid 
is very abundant in the vegetable kingdom, being found in many 
fruits. Used under Vaughn's patent in coagulating Balata. Vul- 
canized rubber immersed in Tartaric Acid at 140° F. remained a 
month, and was apparently unharmed. 

TuNGSTATE OF Ammonia. — A crystalline body which is very 
soluble in water and becomes covered with a white bloom on 
exposure to the air. Used with boracic acid, kauri, borax, and 
rubber in the production of the woodite fireproof compositions. 

TuNGSTATE OF SoDA. — Prepared commercially from wolfram 
ore and soda ash; usually contains about 14 per cent, water of 
crystallization; and is in the form of colorless crystals. Mixed 
with a solvent such as methylated ether, it is added to soluble gun 
cotton, castor oil, and gum copal, forming a substitute for India- 
rubber. 

TuNGSTic Acid is derived chiefly from wolfram, which is a 
tungstate of iron and manganese. Tungstic Acid is analogous to 
sulphuric and chromic acid. It has been used in connection with 
paraffine, gelatine, and metallic oxides in proofing compounds. 



CHAPTER XI. 

VEGETABLE, MINERAL, AND ANIMAL OILS USED IN RUBBER COMPOUNDS 

AND SOLUTIONS. 

The use of oils in the rubber manufacture has kept pace fully 
with the use of gums, substitutes, and reclaimed rubber. The 
addition of earthy or metallic or vegetable ingredients in dry mix- 
ing has rendered many a good rubber somewhat intractable — a 
fault which the right oil has often rectified. As a rule, vegetable 
oils are chosen, as they are rarely harmful to the gum. Many 
mineral oils are also freely incorporated in certain compounds. 
Animal oils have always been viewed with more or less sus- 
picion, however, and with good reason, for manufacturers have 
constantly before them rubber goods that have lost their life and 
elasticity through contact with lubricants made of such oils and 
fats. Nevertheless certain of them may be and are used. The 
essential or volatile oils are used to a certain extent in rubber 
manufacture. These oils, as a rule, are liquids which give the 
peculiar odors of plants from which they are derived. Their use 
in rubber is to impart to it a pleasing odor. 

Aluminum Lanolate. — ^This is a product of French Wool 
Grease (which see), made by adding a solution of alum. After 
the addition of the alum, it falls in a brown precipitate. It is then 
dissolved in mineral oil, forming a jelly-like mass which is said to 
compound readily with either India-rubber or Gutta-percha, and 
is soluble in any of their solvents. It is possible that this may 
have some both softening and preservative influences on India- 
rubber, as is claimed, but it should be used with considerable 
caution. 

Anhydrous Paraffine Oil. — Water-free paraffine oil 
(which see). 

Birch Oil. — The fine white bark of the birch tree yields 
a red oil, nearly one-fourth of which consists of the sap phenol, 
which gives the well-known odor to Russia leather. The residue, 
or green part of the birch, yields neither acid nor alkaloid, and 
forms with alcohol a fluid solution which, when once dried, is 
unacted on by alcohol. It is chiefly Obtained from northern 

207 



2o8 OILS IN RUBBER COMPOUNDS. 

Europe and Siberia, and has recently been made also in Germany 
and Austria, where it is known as Jackten oil. This substance 
will unite with the most brilliant colors, and has been used in 
France for waterproofing textile fabrics. In connection with shel- 
lac, resin, and aniline, it is used in the form of a substitute for 
Gutta-percha in insulation. 

Blown Oils. — These are prepared by heating fixed oils in a 
jacketed kettle and blowing a current of air through the fluid. 
Under this treatment, oils become much more dense and also vis- 
cous; indeed, in many physical aspects, they resemble castor oil, 
but differ in that they can be mixed with mineral oils and as a 
rule are not easily soluble in alcohol. Blown oils made from lin- 
seed oil, rape oil, poppyseed oil, and cottonseed oil are sometimes 
used in the manufacture of rubber substitutes instead of the raw 
oils. Known also as Thickened Oils, Base Oils, Soluble Castor 
Oil, etc. 

Bone Oil is obtained by the distillation of animal gelatinous 
substances, principally in the calcining of bones for the prepara- 
tion of boneblack. Its specific gravity it 0.97. It is sometimes 
called Dippel's Oil (which see). 

Camphor Oil. — A liquid of a light reddish brown with a 
yellowish tint, a strong odor like camphor, and a bitter camphor- 
like taste. Its specific gravity is 0.94. Japanese oil varies in 
color from colorless through pale straw, yellow, to black, and has 
a specific gravity of 0.898 for the colorless to 0.99 for the very 
dark. This oil is used in the manufacture of celluloid varnishes, 
paints, lampblacks, etc. It is used also as an adulterant for such 
oils as sassafras oil. It is one of the best solvents for resins, and 
dissolves 46 per cent, of rosin, 9 per cent, copal, and 35 per cent, 
of mastic. 

Caoutchouc Oil. — Made by digesting 55 parts of India- 
rubber in 450 parts of linseed oil. The principal large use for 
this oil is in Germany, particularly in the army, where it was used 
for coating various articles to prevent their rusting. The follow- 
ing substances are found in Oil of Caoutchouc : Eupoine, butylene, 
caoutchoucine, isorprene, caoutchine, and heveene. 

Castor Oil. — A colorless or pale greenish transparent oil, 
very viscous and thickening on exposure to the air. It has the 



COD-LIVER OIL— COTTONSEED OIL. 209 

highest specific gravity of any known natural fatty oil — 0.958. 
It is adulterated frequently with resin oil and rape, linseed, and 
cottonseed oils, especially the "blown" variety. Used in cheap 
proofings without rubber with Kauri gum; also in collodion and 
rubber proofing. It is used in the production of substitutes like 
gum fibrine, and also with chloride of sulphur in producing amber- 
colored substitute. 

Cholesterin. — See Lanichol. 

Cod Oil or Cod-Liver Oil is obtained from the livers of 
codfish. Newfoundland and Norway are the principal manufac- 
turing points. The finest is a very pale, clear, golden yellow, the 
color deepening to a brown in the second and third grades. Its 
specific gravity is 0.923 to 0.929. One part of oil is soluble in 
from 40 to 20 parts cold alcohol, or 30 to 17 parts hot alcohol. 
The lower grades are the more soluble. It is much adulterated. 
Is compounded with India-rubber, beeswax, linseed oil, litharge, 
and asphalt as a waterproofing for leather and with India-rub- 
ber, beeswax, and turpentine as a dressing for hides. 

Colza Oil. — See Rape Oil. 

Consolidated Oil. — See Stearine. 

Corn Oil (also known as Maize Oil). — Made from the seed 
of Indian corn, the plant known botanically as Zea mays. There 
are two processes of manufacture: (i) in which the seed germ is 
pressed before it is used for the manufacture of starch, which 
produces oil of a golden yellow color, and (2) where it is 
recovered from the residue of the fermentation vats where the 
com has been used in the production of alcohol. This oil is dis- 
solved sparingly in alcohol, but very readily in acetone. The oil 
is almost without drying powers. Neither boiling nor the addi- 
tion of lead when boiling gives it definite drying properties. If 
it is heated, however, and a current of air passed through it, and 
manganese borate mingled with it, it dries after a fashion. It is 
largely used at present in the manufacture of what are known as 
Corn-oil substitutes. 

Cottonseed Oil is made from the seeds of the cotton plant, 
usually the Gossypium herhaceum. The crude is of a ruby red 
almost black color. The refined is pale yellow and possesses a 
pleasant nutty taste. It is a semi-drying oil, and is rarely adul- 



210 OILS IN RUBBER COMPOUNDS. 

terated except when linseed oil is very cheap. On standing it 
deposits stearine in waxy flakes. Much used in making substi- 
tutes for rubber. It is also used in the production of artificial 
elaterite, and with paraffine oil for canvas proofing. For Cotton- 
seed blown oils see Blown Oils. 

Creosote Oil is a distillate from wood tar. It is an oily 
liquid with a smoky taste, and is antiseptic. It should be color- 
less but is usually yellow or brown, due to impurities or to ex- 
posure. The best is made from the beech. A similar oil is 
distilled from coal tar. Mixed with red oxide of mercury it has 
been used to coat the fabric of which cotton hose is made as a 
preservative; with India-rubber and sulphur it has also formed 
an insulating compound for telegraph wires. It is used in some 
rubber works where it is arranged that the fumes of the naphtha 
are carried off into it, which it rapidly absorbs, to be later re- 
covered by distillation. 

Essence of Petroleum. — Obtained during the refining of 
Petroleum, and known also as petroleum, vaseline, petroleum 
jelly, etc. (See Vaseline.) 

EucALiPTiA. — A fragrant, refreshing volatile oil. It is 
prepared from eucalyptus oil. 

Eucalyptus Oil. — An aromatic oil found in the leaves of 
the Eucalyptus globulus in Australia. The odor of the oil is 
extremely pleasant, smelling not unlike oil of verbena. This oil is 
said to be most advantageous, used in small quantities in connec- 
tion with solvents for India-rubber, as it tends greatly to accel- 
erate complete solution. It also breaks down refractory samples 
of the gum and renders all of the compound homogeneous. It 
is said that one-third of the time may be saved if from 4 to 6 per 
cent, of this oil is used in the solvent. It is especially good for 
low-grade gums. It has also great solvent power on all resins 
and gums, including India-rubber and Gutta-percha. With the 
addition of a little methylated spirit it will dissolve even kauri 
gum, cold. It is also used in dissolving asphalt for photograph 
varnish. 

Fish Oil. — Obtained from all parts of the bodies of common 
fish by boiling. Fish whose livers yield oil commercially do not 
give Fish Oil, and those bodies that yield oil, do not give liver 



GLYCERINE. 2ii 

oils. Principally prepared from Menhaden. Its specific gravity 
varies between .915 and .930. Fish Oil is used in the manufacture 
of the substitute known as volenite. It is used, however, only as 
a vehicle for carrying resin into the fiber, being afterwards 
wholly removed. 

French Wool Grease. — See Lanoline. 

Glycerine. — A clear liquid of oily sweet taste, without odor. 
When pure it has a specific gravity of 1.26. The Glycerine of 
commerce is a by-product of the soap manufacture, chemical 
reaction occurring when the fat is treated with a caustic 
alkali, giving rise to a compound of a fatty acid and alkali 
to form a soap, while the Glycerine is at the same time lib- 
erated and goes into solution. Glycerine is not acted upon by 
oxygen, and therefore more closely resembles mineral oils, such 
as are used in rubber mixing, than it does the drying oils that go 
to make up substitutes. It has absolutely no solvent action on 
rubber. 

A recent German patent calls for the addition of Glycerine 
because of its oil resisting qualities. In the compound used are 6 
pounds of rubber, and i pound of Glycerine, together with whit- 
ing, litharge, and sulphur. A soap made of Glycerine and an 
alkaline fluid is also used as a cleaning and polishing medium in 
the last stages of the manufacture of certain cut sheet goods. 
Glycerine combined with gelatine and borax has been used as a 
wash for both black and red rubber surfaces. 

Glycerine was the basis of a well-known deodorizing com- 
position for India-rubber, the other ingredients being of an alka- 
line nature. A bath of Glycerine has also been used for experi- 
mental work in vulcanizing India-rubber, and also for rubber 
stamp making. In this kind of work, the mold and its contents 
are immersed in the Glycerine so that the liquid just covers the 
top of the mold; heat is then applied to the Glycerine, and the 
mold in turn becomes hot and the rubber vulcanizes. It is also 
used to a certain extent in good grades of white rubber, as it gives 
a softened effect to the compound. Glycerine, in connection with 
glue, gelatine, molasses, and tannin, is used in the manufacture of 
puncture fluids for tires. It is also used in clothing compounds, 
and in cellulose products like pegamoid. Used in rubber, a little 



212 OILS IN RUBBER COMPOUNDS. 

of it increases the resiliency of the product. Another use for 
Glycerine is to prevent fabrics from mildewing. The fabric is 
coated with it before being frictioned. 

Hydrolene. — A rubber assistant used in connection with the 
reclaiming of rubber, and also rubber compounding. It would 
seem to be a petroleum product, and in rubber reclaiming is used 
instead of stock oil or residuum. 

Japan Wax. — A white or pale yellow vegetable fat, with a 
specific gravity of 0.97 to 0.98. It is used in wax matches, 
candles, and for adulterating beeswax. A special use for it, that 
has arisen within the last few years, is in the manufacture of 
cravenette cloths. 

Lallemantia Oil is obtained from the seeds of the Lalle- 
mantia iberica, a plant cultivated in Russia. This is one of the 
best drying oils, being said to surpass even linseed oil, but its 
chief use is for illuminating purposes. In Europe it is said to 
have been used instead of linseed oil in rubber substitutes. 

Lanichol. — A product of lanoline (which see), made from 
the oil' of sheep's wool. It combines with Gutta-percha and India- 
rubber in any proportion to a perfectly homogeneous mass. This 
grease does not oxidize and is wholly antiseptic. It has no smell, 
and is impervious to the action of alkalies or to dilute sulphuric 
acid. It is said that, used in connection with Gutta-percha, the 
melting point is considerably raised, while it does not diminish 
the insulating property. An insulating compound given is 50 
parts by weight of Gutta-percha, 30 parts of India-rubber, 20 
parts Lanichol. The inventor claims that it renders Gutta-percha 
less liable to oxidation, improves its elasticity and tenacity, and 
diminishes its liabilty to become sticky. Patented in the United 
States and Great Britain by Robert Hutchinson. 

Lanoline is also known as wool grease, recovered grease, 
and brown grease. It is the natural grease found in sheep's wool 
and recovered from it while the raw wool is being prepared for 
spinning. A similar grease, made from scoured woven goods, is 
known as Yorkshire grease. It is a thick yellow or brown offen- 
sive smelling greasy paste. Commercial Lanoline is lighter 
colored and consists of about 80 per cent, of pure wool fat and 20 
per cent, of water. It possesses in a remarkable degree the 



■ LAN OLINE— LINSEED OIL. 2-13 

property of taking- up water without losing its vaseline-like con- 
sistency. Is largely used in ointments. 

Lanoline, mixed with India-rubber, works up into an exceed- 
ingly sticky mass, and is used as a medicinal plaster. It is said 
that, while it possesses the adhesive properties of the regular' 
plaster, Lanoline takes up the medicament, and while very sticky 
can be readily removed from the skin. It is used for the purpose' 
of softening India-rubber, and was advised for use in tires, as it 
was said to soften the compound, and to keep the tire from decay, 
and from consequent surface cracking. It was also said to be 
used in boot and shoe work. 

Lard Oil is prepared by the cold pressing of lard, which, of 
course, is the fat of the hog. It is a colorless, limpid liquid, 
although poorer grades are brown. Its specific gravity is 0.915. 
It is frequently adulterated with rape oil and cottonseed oil. Lard 
Oil, mixed with powdered pumice stone into a thick paste, is used 
for polishing hard rubber. 

Linseed Oil is pressed from the seeds of the flax plant 
(Linum usitatissimum) , grown chiefly in India, Russia, and 
Argentina. The trade recognizes two qualities of Russian seed — 
yielding the Black sea Linseed Oil, and the Baltic Linseed Oil — 
while that coming from India is known as East India Oil. Of 
these, the Baltic is the best, and the East Indian the poorest in 
quality. The two lower grades are not up in quality for the 
reason that the Black sea seed contains a certain amount of hemp 
seed, while that from India is usually mixed with rape, camelinc, 
and mustard seeds. The oil which is expressed from these seeds 
is of a golden yellow color, with a peculiar taste and odor. Lin- 
seed Oil becomes easily rancid in the open air, but when spread 
in thin films dries into an insoluble substance which has been 
called linoxyn. Linseed Oil is adulterated sometimes by fish or 
mineral oils, and by resin oils. Old tanked Linseed Oil is used in 
the preparation of what is known as boiled oil ; that is, it is heated 
in a high temperature that it may more rapidly dry when used in 
varnish. This drying process is hastened by the addition of man- 
ganese dioxide, litharge, etc. Boiled Linseed Oil is much darker 
than raw oil, having a brown red shade. It is also much more 
viscous and has a higher specific gravity. Boiled oil is adulterated 



214 OILS IN RUBBER COMPOUNDS. 

in the same manner as is raw Linseed Oil, the adulterants being 
resin oils, resin, and mineral oils. 

In rubber compounding Linseed Oil is very often used. A 
very simple formula for waterproofing canvas is India-rubber, 
litharge, sulphur, and Linseed Oil. It is also used in rubber var- 
nishes, to a certain extent in molded goods, and quite largely in 
hard rubber compounding. It is used in the manufacture of rub- 
ber substitutes, and is well known as it is the basis of a great 
many of the vulcanized oil substitutes. Linseed Oil that is in- 
tended for mixing in linoleum is exposed to the air until it is 
thoroughly oxygenated. In this state it is insoluble in alcohol, 
chloroform, ether, and ordinary solvents. 

Lithographic Varnish is obtained by boiling linseed oil at 
a temperature higher than that at which boiled oil is prepared, 
nor are dryers added during the boiling. It is a perfectly clear, 
transparent substance, the best quality being nearly as light as 
raw linseed oil. There are two ordinary grades of Lithographic 
Varnish. One is known as "burnt oil," which is obtained by 
bringing raw linseed oil up to its flash point, and allowing it to 
bum until the required thickness is reached, it being constantly 
stirred meanwhile. "Oxygenated oil" is a linseed oil varnish 
made by treating the oil with oxygen in jacketed kettles, heated by 
steam. The product is as light colored as raw linseed oil, but 
heavier. It is also more readily soluble in alcohol, and has marked 
drying powers. 

Manganated Linseed Oil is used in certain rubber com- 
pounds where more of a drying effect is needed than is found in 
the raw linseed oil. It is linseed oil that has been boiled with 
peroxide of manganese to increase its drying qualities. (See 
Boiled Oil.) 

MiRBANE Oil. — See Nitrobenzene. 

Mustard Oil. — Black Mustard Oil is obtained from the 
seeds of the Sinapsis nigra. It possesses a mild taste, is of a 
brownish yellow color, and in its chemical composition closely 
resembles rapeseed oil. It is a by-product and is largely used in 
soap making. White Mustard Oil is made from the seeds of the 
Sinapis alba. It is of a yellow color, and is almost identical with 
black Mustard Oil. Used in making rubber substitutes. 



NEATSFOOT OJL-^OIL OF TAR. 215 

Neatsfoot Oil. — A pale, yellow, colorless oil, obtained from 
like feet of oxen by boiling in water. It has a smooth pleasant 
taste. On standing it deposits stearine. It is largely adulterated 
with cheaper animal or vegetable and even mineral oils. Neats- 
foot Oil, mixed with Gutta-percha, tallow, sweet oil, and oil of 
thyme, is used as a rust preventive. It is used in connection 
with beeswax. India-rubber, and Burgundy pitch in a composition 
for dressing leathers or hides. 

Nitrobenzene (also called Oil of Mirbane and "imitation 
oil of bitter almonds") is a yellow aromatic liquid produced by 
the action of nitric acid on benzine. It is used in perfumery and 
turned out in great quantities for the manufacture of anilines. 
It is used also in certain insulating compounds in connection with 
asbestos, powdered glass, vulcanized rubber, castor oil, resin oil, 
and celluloid in solution. 

Oil of Lavender has no perfume when new, but develops 
it on being exposed to the air. It is distilled from the flowers of 
the Lavandula vera, and is used sometimes to deodorzie rubber 
goods. 

Oil of Lemon is obtained from fresh lemon peel. A very 
volatile yellow or colorless oil ; specific gravity of 0.858 ; soluble in 
bisulphide of carbon, and absolute alcohol ; often adulterated with 
fixed oils and alcohol; dissolves sulphur, phosphorus, resin, and 
fats; used to deodorize certain proofing compounds, cologne 
sometimes taking its place. 

Oil of Orris, or Orris Oil, is found commercially and is 
prepared from the root. It is lighter than water, and of the con- 
sistency of butter. Melts at 100° F., and is miscible with alcohol. 
Its odor is like that of violets. Is used in rubber as a deodorizer. 

Oil of Peppermint. — A greenish yellow colorless oil, be- 
coming reddish with age; of a strong and aromatic odor; and 
warm, camphor like, very pungent taste; specific gravity from 
0.902 to 0.920 ; used in fine goods for its color. 

Oil of Rosemary. — An essential oil of the specific gravity 
0.896. Colorless and having the odor of rosemary. Used with 
India-rubber, parafiine, and spermaceti in waterproofing com- 
pounds, and, where rubber is present, to neutralize its odor. 

Oil of Tar. — An oil distilled from tar. It is a mixture of 



2i6 OILS IN- RUBBER 'COMPOUNDS. 

several lighter oils, and is made up of liquid hydrocarbons which 
hold in solution small quantities of anthracine, napthaline, and 
paraffine. It is sometimes used for mixing with lubricating oils, 
and for coating bags that are to hold alkaline earths, the interior 
of the bag being washed with chloride of lime. The Earl of Dun- 
donald recommended Oil of Tar as a coating for rubber, claiming 
that it had a preservative effect. It is also used in compounds 
for surface clothing. 

Oil of Thyme (also called Origanum Oil) is extriacted 
from the flowers and leaves of the Thymus vulgaris. It is yel-" 
lowish red in color ; its specific gravity is 0.92 ; and it has a pun- 
gent taste ; it is used to disgitise the odor of ale cements. 

Oil of Wormwood. — A pungent essential oil distilled from 
the Artemisia absinthium: employed at an early day to deodorize 
spirits of turpentine when used in rubber. 

OleaRgum. — A black viscid liquid of an oily nature used as 
a dull finish wash for rubber boots. Its composition is a trade 
secret. 

Oleum Succini. — The sam.e as Oil of Amber (which see) ; 
used in the manufacture of soap substitutes. 

Olive Oil is expressed from the fruit of the olive tree, prin- 
cipally in the countries of Europe bordering on the Mediterra- 
nean. Its specific gravity is 0.916. It is adulterated frequently 
with cottonseed oil. Olive Oil is used in taking impressions from 
type faces in the matrix in which rubber type is cured. Mayall 
suggested the mixing of Olive Oil with clay until it formed a 
soft putty, and then incorporating it with India-rubber, the 
proportion being -J pound of oil to 30 pounds of gum. The use 
of the oil enabled the goods to be more largely adulterated ; he 
also used Olive Oil in connection with devulcanized rubber, not as 
a solvent, but because he claimed that it combined with the gum 
and improved its quality. Olive Oil is also used in hard rubber 
compounding. Rubber is sometimes heated up in Olive Oil mixed" 
with zinc, soap, and borax for a proofing solution. It is also used 
in the manufacture of pegamoid. 

Palm Oil is obtained from the fruit of various species of 
palm, principally from the west coast of Africa, and is known in 
commerce under as many names as there are ports of shipment. 



PALM OIL—PETROLA TUM:' ' iiy 

It is expressed in a very rough fashion by the natives, who stir 
the palm kernels in holes in the ground until fermentation sets in 
and the oil rises to the surface. They also sometimes press the 
oil from the fresh fruits. The harder grades of Palm Oil are 
yielded by the former process, the latter giving the finer oils. 
Palm Oil varies in consistency. Its specific gravity is 0.945 ; its 
color yellow to reddish ; its odor that of violets. It yields a soap 
readily with alkalies and dissolves in ether and in alcohol of 0.848 
specific gravity. Palm Oil is very rarely adulterated, unless it is 
done by the native gatherers, who sometimes add sand as a make- 
weight. Commercially, where sand and water together exceed 2 
per cent., an allowance is claimed from the seller. 

White Palm Oil is that which has been bleached by heated 
chemicals or exposure to the air. "Lagos oil" has about the same 
consistency as butter, while "Congo oil" is as thick as tallow. 
Palm Oil is used largely in the manufacture of mechanical and 
dry-heat goods, chiefly to enable dry ingredients to mix more 
easily with India-rubber. It has also been used in the recovery 
of waste rubber by the mixing of the finely ground rubber with 
it and exposing the mass to a heat of 572° F. Palm Oil residuum 
is used in connection with resin oil as an insulator. Palm Oil is 
also used in the production of artificial elaterite. 

Paraffine Oil is a petroleum product; it may also be pre- 
pared from coal tar and wood tar. It is a waxy substance of a 
white color, much resembling spermaceti. It is used chiefly as a 
lubricant, and is not acted upon by most of the chemical reagents. 
Paraffine Oil mixed with cottonseed oil is used in certain canvas 
proofings. 

Petroleum Oil (also known as Rock Oil) is a dark, ill- 
smelling liquid, obtained from wells sunk in oil-bearing sands. 
Some Russian oils, however, are colorless. White Rangoon oil 
contains so much paraffine as to have the consistency of butter. 
The specific gravity of American petroleum varies from 0.8 to 
0.85 or 0.9. 

Petroleum Paraffine. — See Vaseline. 

Petroleum Jelly. — See Vaseline. 

Petrolatum is a rubber compounding ingredient very gen- 
erally used, especially in mechanical goods. It is one of the 



2i8 OILS IN RUBBER COMPOUNDS. 

numerous products of petroleum or rock oil derived by distilla- 
tion. These products are classed as follows : Light oils, includ- 
ing gasoline and naphtha ; illuminating oils, kerosene ; residuum 
or tar. From the latter subdivision is separable, by further in- 
crease of heat, heavy lubricating and parafiine oils, among which 
are petrolatum or vaseline, and coke as a waste product. 

Petrolatum gains much of its value from its indifference to 
volatile oils. It is separated from the residuum of crude petro- 
leum which has been subjected to the vacuum process of distil- 
lation in contradistinction to the "cracking" process by which 
some of the natural constituents are chemically broken up to form 
new bodies. The residuum being kept fluid by steam, the finely 
divided coke resulting being the distillation is allowed to settle 
out and the clear oil drawn oflf and filtered through bone charcoal 
contained in cylinders, in order to remove the color and odors 
contained in it. Sometimes the oil recovered from the residuum 
is treated with sulphuric acid and potassium bichromate for the 
removal of certain impurities before the filtration through bone 
charcoal. This is said to be the German process. 

Petrolatum gains much of its value from its indifference to 
all chemical treatment, thus resembling paraffine very closely. 
It is generally familiar as a dense product, pale yellow, trans- 
lucent, slightly fluorescent, semi-solid melting at about ioo° F., 
and having a specific gravity of 0.850. Its chemically inert quality 
peculiarly adapts Petrolatum to use in rubber compounding where 
a non-oxidizing lubricant and softener is needed to facilitate the 
manipulation of harsh or dry compounds, and which will not sub- 
sequently develop in the finished goods injurious or other incon- 
venient qualities. Simple softening of rubber any oil will 
accomplish, but for all around adaptability Petrolatum excels all 
others. 

Ordinarily 2 or 2^ per cent, of Petrolatum is sufficient in any 
compound where its presence is needed, although 5 or even 7 per 
cent, may be employed in special cases. Cheap goods containing 
Petrolatum will withstand drying out or hardening with age, a 
similar effect being produced by the use of soft coal tar. As 
regards the item of economy. Petrolatum commends itself to the 
rubber manufacturer when considering the use of an oil ingre- 



POPPYSEED OIL— SHALE OIL. 219 

dient in compounding. For all ordinary purposes, everything 
except perhaps the whitest goods, the dark filtered stock is entirely 
suitable and the price will be less than the light filtered stock. 

PoppYSEED Oil is obtained by pressing the seeds of the com- 
mon poppy (Papaver somniferum). Commercially there are two 
grades, white and red. This oil has a pleasant taste and no odor ; 
it is rarely adulterated with other oils, although occasionally 
sesame oil is found in it; it is an excellent drying oil, and its 
lower grades are used in the manufacture of soaps ; its use in the 
rubber industry is chiefly in the manufacture of substitutes. 

Rapeseed Oil (also known as Colza Oil) is a pale yellow in 
color, with an unpleasant harsh taste. Its specific gravity is about 
0.916. It is largely adulterated with vegetable, mineral, or 
fish oils. It is obtained from the seeds of the Brassica campestris, 
and of several varieties of this genus which are cultivated. 
American oils from all of these are termed Colza or Rape Oil in- 
discriminately. In Europe, however. Rape is one kind of oil and 
Colza is another. There is also what is called the summer oil and 
the winter oil, a distinction which is of no interest to rubber 
manufacturers. Rape oil is hardly a semi-drying oil, nor is it yet 
a non-drying oil, but about half way between the two. It is used in 
the manufacture of certain rubber substitutes. Mixed with India- 
rubber it has been used as a somewhat costly mixture for lubri- 
cating machinery. 

Rosin Oil. — Made by subjecting resin to destructive distil- 
lation. The resultant oil is heavier than mineral oils, and its 
chemical composition is quite involved. It is largely made up, 
however, of hydrocarbons, with a certain amount of resin acids. 
Used in making a waterproof solution, by the addition of Japan 
wax and gum thus, in the manufacture of a solution for treating 
hides and leather. Used also in compounds for calking ships in 
which India-rubber has a part, and is an important ingredient in 
the manufacture of guttaline. (See Rosin.) 

Russian Mineral Oil. — Petroleum from the Baku oil wells. 

Shale Oil. — Chiefly produced in Scotland from a dark, 
coal-like looking material called shale. It is similar in nearly all 
respects to petroleum oil. Used with asphaltum in certain insu- 
lating compounds. 



220 OILS IN R VBBER-- CO'MPO UNDS. 

Sludce. — The brown or black residue obtained in the defin- 
ing of petroleum after all the lighter oils have been distilled off: 
Known also as Petroleum Residuum. (See Sludge-oil Resin.) 

Stearine. — An important ingredient in animal and- vege- 
table fats. It is quite solid, and increases the hardness, and raises 
the melting point of fat. Commercially, Stearine is also known ag 
stearic acid. It is an important element in the manufacture of 
cravenettes, where it is used with ozocerite, beeswax, paraffine, 
and Japan wax. 

TalloVi'. — Beef tallow, when fresh, is almost white, free 
from disagreeable odor, and almost tasteless. On the other hand, 
foreign tallow runs from white to yellow and is often quite ran- 
cid. Tallow is often adulterated with resin oil, cocoanut oil, cot- 
tonseed oil, and paraffine wax. It is used in non-drying cements 
in connection with slaked lime and India-rubber. In connection 
with India-rubber it is also used in the production of what was 
known as Derry's waterproof harness oil, which was made of 
India-rubber, Tallow, seal oil, and ivory black. An etching var- 
nish is made of Gutta-percha, turpentine, beeswax, and Tallow. 
A small amount of this was used by Hancock in compounding 
for softening Gutta-percha. It is used with Gutta-percha in shoe- 
makers' wax, and also in certain proofing compounds with India- 
rubber, pitch, and linseed oil. Mixed with India-rubber, beeswax, 
and linseed oil, Tallow makes an excellent dressing for leather. 

Turpentine was used in one of the earliest formulas in the 
manufacture of devulcanized rubber. (See Spirits of Turpentine.) 

Vaseline is the purified residue from the distillation of 
petroleum. Its specific gravity is .875 to .945. It is insoluble in 
water, barely soluble in cold, but soluble in boiling absolute alco- 
hol, and in ether, bisulphide of carbon, oil of turpentine, benzine, 
and benzol. It is the basis of a cheap waterproofing process, the 
other ingredients being silicate of soda, alum, and hot water. 
Vaseline is used quite often in general compounding for its soft- 
ening efifects. It is also combined with menthol and gum ali- 
banum in the manufacture of porous plasters. Vaseline has been 
iised in the manufacture of substitutes similar to ruberite. (See 
Petrolatum.) 

Vulcanized Oil. — See Rubber Substitutes. , ■ 



WALNUT OIL. 221 

Walnut Oil. — Cold drawn oil is very fluid, almost colorless, 
and of an agreeable nutty flavor. Hot pressed oil has a greenish 
tint and an acrid taste and smell. Is used in rubber substitutes, 
particularly in those in which peroxide of lead appears as a dryer. 

White Drying Oil. — Bleached linseed oil. 



CHAPTER XII. 

SOLVENTS USED IN INDIA-RUBBER PROOFING AND CEMENTING AND IN 
COMMERCIAL CEMENTS. 

The beginnings of the manufacture of India-rubber con- 
sisted in putting the gum in solution and it was a considerable 
time before the discovery of the present processes of dry mixing, 
which are employed in the production of the greater part of the 
rubber goods now made. There are certain lines, however, where 
the use of solvents is still both necessary and economical. In the 
mackintosh manufacture, for instance, the rubber is in almost 
every instance spread in the form of solution, as a thinner coat 
can be spread in this way, offsetting the cost of the solvent. Many 
sheetings in various colors that, only a few years ago, were calen- 
dered, are now coated by the means of solution. In the making 
up of almost all lines of rubber goods, certain cements are neces- 
sary, and these are ordinarily made in the factory that produces 
the goods. The cements that are sold in bulk, such as channeling 
cements, for leather shoe manufacturing, as well as cements that 
are sold in smaller packages to repair men in the cycle industry, 
all consist of rubber and analogous gums treated with some suit- 
able solvent. Before discussing the ordinary and the extraor- 
dinary solvents that interest the rubber manufacturer, it may be 
well to consider what the various solvents can do. 

The following tables showing the solubility of India-rubber 
are of exceeding interest, therefore. The first, which is taken 
from the Journal of the Society of Chemical Industry, is a table 
of the solubility of masticated caoutchouc in solvents : 

Ceara Para Sierra Leone 

100 parts of : Rubber Negroheads Rubber 

Ethyl ether 2.6 3.6 4.6 

Turpentine 4.5 5.0 4.6 

Chloroform 3.0 3.7 3.0 

Petroleum benzene 4.4 5.0 j 1 7 

Carbon bisulphide 0.4 None. None. 

Hoffer gives, as a result of his individual experiments, the 

following table of solutions, the samples in each case being 100 

parts of well-dried India-rubber: 

222 



RESINS IN RUBBER. 223; 

In bisulphide of carbon 65 to 70 

In benzol 48 to 52 

In oil of turpentine 50 to 52 

In caoutchine 53 to 55 

In ether 60 to 68 

In camphene 53 to 58 

The great differences in solubility between various grades of 
rubber have been found to be due, as much as anything, to the 
amounts of resins that are to be found in them. As these resins 
are soluble, and in some cases can be removed, it is important that 
rubber manufacturers not only appreciate their presence, but, 
where it is practicable, dissolve them out. These resins, accord- 
ing to Lascelles-Scott, who furnishes the following table, consist 
of abietic acid or some other similar body : 

Normal Resin Normal Resin 

Description of (soluble in Description of (soluble in 

Rubber. 85 p. c. Alcohol) . Rubber. 85 p. c. Alcohol) . 

Para 91 Ceara 1.16 

Para 60 Assam 6.45 

Para 1.62 Assam 4.88 

Para 1.14 Burma 5.20 

Para 85 Rio 3.37 

Madagascar 4.06 Africa (various) 8.23 

Madagascar 5.22 Africa (various) 10.60 

Madagascar 2.84 Africa (various) 6.71 

Colombia 3.40 Mangabeira 8.43 

Colombia 2.11 Origin unknown 11.14 

Ceara 2.33 Origin unknown 7.27 

Ceara 1.80 Origin unknown 16.56 

In some of them oxygen is a component part, and they are 
all soluble in alcohol of 85 per cent, strength and upwards. It 
will be noticed from this table that Para rubber has the least per- 
centage of resin, and, of course, is the most valuable. The 
samples containing the largest proportions of resin were unmis- 
takably adulterated with other gums during collection. 

C. O. Weber gives the percentages of resin in a number of 
samples of rubber as follows : 

Per Cent. Per Cent, 

Grade of Rubber. Resin. Grade of Rubber. Resin. 

Para (fine) 1.3 Sierra Leone 9.7 

Ceara 2.1 Assam 11.3 

Colombian 3.8 Mangabeira 13.1 

Mozambique 3.2 African ball No. i 22.8 

Rio Janeiro 5.2 African ball No. 2 26.1 

Madagascar 8.2 African flake 63.9 

The patent of Frankenberg (English) covering the produc- 
tion of non-inflammable solutions of rubber is of exceeding 



224 SOLVENTS' FOR R UBBER. 

interest as suggesting the use of new and safe solvents. To-day 
few chlo'rhydrins are used, because of their expense, but a num- 
ber of them are on the market and the cost is steadily being 
reduced. Frankenberg's solutions are produced by mixing rubber 
with carbon tetrachloride, dichlor-methane, trichlor-ethane, tetra- 
chlor-ethane, or trichlor-benzol, alone or together. The rubber 
may be softened with coal-tar naphtha or other solvent before 
the above solvents are added. 

Acetone is a colorless mobile liquid, with a very unpleasant 
taste and peculiar odor, and outwardly resembling alcohol. It is 
a good solvent for many organic substances, and for many gums 
and resins. Acetone is produced by the destructive distillation of 
acetate of lime, which is one of the chemicals made from the 
products of wood distillation. It has a specific gravity of .80 and 
boiling point of 134° F. It is a solvent for rubber resins dis- 
solving about 18 per cent, of Pontianak resin while hot and is 
recommended as a solvent for use in analysis of rubber, as it is 
without action on the gum. 

Alcohol, when pure, is a colorless, thin, mobile liquid, of a 
somewhat disagreeable smell, burning taste, and specific gravity 
0.792. What is known as absolute Alcohol is that which has been 
deprived of all water. Its specific gravity is 0.795. It eagerlv 
absorbs water, and, as it becomes more dilute, its specific gravity 
rises ; Alcohol of 60 per cent, has a specific gravity of .883. There 
are a number of forms of alcohol used in the arts. Alcohol, 
chemically considered, embraces a large class of similar bodies. 
Wood Alcohol or methyl Alcohol is made from the products of 
wood distillation, is a colorless mobile fluid with a specific gravity 
of .80 and a boiling point of 150° F. and is poisonous. It is a 
good solvent for many resins, but dissolves Pontianak resin 
scarcely at all. Some of the resins of other rubbers are attacked 
slightly by it. Grain Alcohol is the product of the fermentation 
of starch or sugar and in the United States is made largely from 
corn, rye, and molasses. It is chemically termed ethyl Alcohol 
and is the next in series above wood Alcohol. Its boiling point 
is 170° F. and its solvent powers for resins of rubber is greater 
than that of wood Alcohol, but some other resins are less soluble 
in the grain Alcohol. It can be brought to a purity of only 96 



ALCOHOL. " 225 

per cent, by ordinary distillation, and this grade is known as 
cologne spirits or neutral spirits. It does not dissolve rubber or 
sulphur, except the "beta" modification which crystallizes in 
yellow prisms. Dissolves readily in benzol but not in petroleum 
benzine except slightly. Dissolves fatty acids but not fats or fatty 
oils except castor oil. Soluble in most rubber solvents or dissolves 
them. Grain or ethyl Alcohol is the most commonly used Alcohol 
and is usually the one referred to unless others are specified. 

Denatured Alcohol is merely grain Alcohol to which have been 
added small quantities of substances which render it poisonous 
and undrinkable. The most common formula for denaturing 
Alcohol is 5 per cent, wood Alcohol and J4 per cent, petroleum 
naphtha or gasoline. Many other special formulas are allowed. 
When so denatured it may be removed from the distillery without 
the payment of the government tax of $1.10 per proof gallon or 
$2.90 per gallon of 95 per cent. 

Fusel oil consists of higher Alcohols and is obtained in the 
manufacture of grain Alcohol. It is insoluble in water and a 
solvent of many gums and of pyroxylin or celluloid. Other sub- 
stances, for example, phenol and glycerine, are chemically alcohols, 
but are not so called in commerce. 

None of these really are solvents of rubber, but are frequently 
and largely used in varnishes. India-rubber solution, when 
treated with large quantities of Alcohol, is deposited in a spongy 
form, the foreign ingredients in the gum going into the solution. 
Treated in this way it can be made an exceedingly white mass. It 
is also used in treating many of the pseudo guttas to dissolve out 
the brittle resinous matters. It has also been claimed that the wash- 
ing of raw rubber with Alcohol dissolves resinous ingredients 
which are better absent, and that the rubber as a result lasts 
longer. Rectified spirit is what is generally known, or rather, 
used, in connection with India-rubber. It is used by the gatherers 
to coagulate the latex of the Balata, and is used also in the produc- 
tion of resinolines (which see). One of the early uses was to 
mix with it various solvents — for instance, with spirits of tur- 
pentine, coal oil, bisulphide of carbon, ether, chloroform, etc. 
When ill-smelling solvents were used, it was also often incor- 
porated to neutralize the odor. In the Azo process for reclaiming 



226 SOLVENTS FOR RUBBER. 

rubber, 20 parts of Alcohol to i part of bisulphide of carboti are 
used for softening and reclaiming rubber. Dental and other gums 
are exposed to the sunlight in Alcohol to increase the brilliancy 
of the colors and to make the shades lighter. Alcohol is also 
used to soften vulcanized rubber when a surface color is to be 
added. Alcohol, in connection with nitric acid, spirits of tur- 
pentine, and aniline, was used by Kelly for surface work on 
India-rubber. 

Anthracine. — A trade name for Napthaline (which see). 
Benzol or Benzole is a volatile oil obtained in the distilla- 
tion of coal tar, which must not be confused with petroleum ben- 
zine or petroleum naphtha. Its specific gravity is 0.899 ^^ 3^° F., 
and 0.878 at 68° F. Chemically it consists of 6 parts carbon and 
6 parts of hydrogen and its combinations and products are the 
most numerous and best known of all chemical compounds. It is 
the basis of nitrobenzene and aniline which is the basis of the 
largest part of the coal tar compounds, colors and dyes. Com- 
mercially it is sold as pure, 90 per cent, and 70 per cent. By 
90 per cent. Benzol it is meant that 90 per cent, will distill over at 
the temperature of boiling water and likewise with 70 per cent. 
The commercial Benzol is to a great extent obtained from the 
Hquid which settles out from compressed Pintch gas. The com- 
mercial article is a mixture of Benzol with higher boiling bodies 
which are very similar in their chemical properties, and these bodies 
are mostly toloul or toulene which boils at 232° F. and xylol or 
xylene which boils at 287° F. and higher boiling homologues. It is 
slightly soluble in water, and freely soluble in alcohol and ether, 
and in bisulphide of carbon. It has great solvent properties. Benzol 
(is used largely as a solvent for rubber in manufacturing bicycle 
cements, and also for dissolving rubber, and for the cold vulcani- 
jzation of thin rubber fabrics containing chloride of sulphur, in 
', which Benzol is much superior to carbon bisulphide ; and at pres- 
■ ent it is much cheaper, both on account of less loss in handling, 
and also, of its much lower price per gallon. This refers more 
particuarly to the high grades of Benzol, like 100 per cent, or 
C. P. ; the 160° Benzol is mostly used where a solvent is required 
that must not evaporate too rapidly. It is said that if Gutta- 
percha is put in 20 times its weight of boiling Benzol, to which 



BISULPHIDE OF CARBON. 227 

one-tenth of plaster is added, and the mixture agitated from 
time to time, a perfectly clear solution is decanted. This is then 
mixed with twice its volume of 90 per cent, alcohol and the 
Gutta-percha precipitated a pure white. (See Naphtha.) 

Bisulphide of Carbon is a transparent liquid, the specific 
gravity of which it 1.27. It is exceedingly volatile, evaporating at 
ordinary temperature. When properly made its smell is some- 
what similar to chloroform. The bad smell found in some is due 
to sulphureted hydrogen, and the presence of foreign matters 
from which it can be thoroughly freed by purification. It is 
highly inflammable, though not explosive, and has great affinity 
for sulphur, 100 parts dissolving 37 parts of sulphur, cold; and 
at 100° F. the same quantity will dissolve 94.5 parts. Bisulphide 
of Carbon mixes with every known substance capable of vul- 
canizing rubber. It also assimilates rapidly with all fatty oils, 
and dissolves all the resins, with the exception of shellac. It does 
not dissolve vulcanized rubber, however. Where it is used in 
rubber factories care is taken, as a rule, to remove the fumes, as 
they are injurious to the workmen. Some very serious cases 
of chronic poisoning have occurred through the use of this sol- 
vent, the symptoms being numbness, partial paralysis, and, in 
some cases, temporary insanity. The use of Bisulphide of Carbon 
in rubber factories is very carefully watched, therefore, by the 
authorities in Europe, proper means for ventilation and carrying 
off the fumes being insisted upon, and minors being excluded 
from rooms where it is used. It is one of the best and most com- 
mon solvents for India-rubber, very largely used in the Parkes 
cold curing and similar processes, and in cements. 

Bisulphide of Carbon Substitute, a liquid produced by 
Dr. Carl Otto Weber, is said to have been a perfect substitute for 
bisulphide of carbon. It had these advantages: less chloride of 
sulphur was needed, the smell of the vulcanized product was 
sweeter, the vulcanizing solution penetrated deeper into the rub- 
ber, the risk of burning the rubber and the uneven vulcanization 
were also done away with. It is also said that this substitute is 
not injurious to the health. It is manufactured in England. 

Borax is sometimes used as a solvent for rubber. (See 
Acids and Alkalies.) 



228 SOLVENTS FOR R UBBER. 

Camphene is a name applied to one of the varieties of spirits 
of turpentine which was once largely used as a burning fluid. It 
is very volatile, and the vapor may exist in the air in explosive 
quantities. Camphene was formerly used to a certain extent as a 
solvent for India-rubber. Under Newton's method of recovering 
rubber, the waste was placed in a closed vessel, covered with 
Camphene, and heated to 158° F. for fourteen days. The solvent 
was then distilled off, and the tough mass remaining was capable 
of utilization, and was somewhat similar to unvulcanized rubber. 
It was also used in the boot heel cements in the old-fashioned 
method of attaching them to rubber boots, and also in general 
shoe cements. Camphene was also used in putting vulcanized 
waste, finely powdered, into a solution in connection with ether 
and alcohol, in a simple but somewhat expensive process of 
recovery. 

Camphor has been used as a solvent for utilizing the waste 
of vulcanized rubber and of hard rubber, the waste being first 
treated with any ordinary solvent and then placed in a still with 
a certain amount of Camphor, when the India-rubber is dissolved 
and the solvent passed out and distilled over again. Granulated 
Camphor, over which had been passed sulphurous acid gas until 
it was reduced to a liquid, was used also as a solvent for India- 
rubber, by Alexander Parkes. (See Gums, etc.) 

Caoutchoucine, also spelled Caoutchine, is a crude oil of 
India-rubber, made by its dry distillation, and smelling much like 
naphtha. It is an excellent solvent for India-rubber, but of course 
is too expensive for ordinary use. India-rubber immersed in it 
swells exceedingly, and a considerable quantity of it is dissolved 
during the boiling. It must be kept in hermetically sealed vessels, 
as it has a great affinity for oxygen, which it absorbs energeti- 
cally. In preparing it, the India-rubber is treated in a retort at 
a heat exceeding 400° F. Caoutchoucine dissolves in ether or 
alcohol, and, absorbing oxygen freely, forms a resinous body as 
a result. 

Carbon Tetrachloride is a heavy, colorless, transparent 
mobile liquid, having a neutral reaction. Its odor is agreeable, 
but poisonous, resembling that of chloroform. It is non-inflam- 
mable and non-explosive. The vapors do not support combustion, 



CARBON TETRACHLORIDE. 229 

but act in the reverse as a fire extingfuisher. The specific gravity 
of Carbon Tetrachloride is 1.6; the boiHng point yy° C. or 170° F. 
The Hquid is insoluble in water, diluted alcohol containing less 
than 75 per cent, by volume of absolute alcohol and also in glycer- 
ine and the glycerides. It is freely soluble in acetone, glacial 
acetic acid, oleic acid, liquid carbonic acid and aqueous solution 
of carbolic acid, ethyl, and amylic alcohol, chloroform, carbon 
disulphide, benzol (Petroleum benzine), ether and aniline, oil of 
turpentine, petroleum and all petroleum products, also in fixed and 
volatile oils and oleoresins. 

It dissolves oils, fats, resins, w^ax, India-rubber, Gutta- 
percha, ceresin, spermaceti, paraffine, stearin, varnish, paints, 
asphaltum, pitch, balsams, coal tar, pine tar, and soda and 
potash soaps. It also dissolves salicylic acid, carbolic acid, 
iodine, bromine, iodoform, bromoform, menthol, thymol, cam- 
phor, camphor monobromate, naphthalin, etc. It further- 
more dissolves several gases, among others ammonia and hydro- 
gen sulphides. It is not acted upon by the strong mineral 
acids and is not decomposed by an aqueous solution of potassa, 
which will, however, remove any carbon disulphide or hydro- 
gen sulphide present. 

It is strongly recommended as an extracting medium. It 
is important to remember that in contrast with benzine, gaso- 
line, etc., Carbon Tetrachloride (C Q4) is a single chemical 
compound, and in its recovery from the extracted fats, grease, 
etc., it is always obtained as the same chemical combination, 
with the selfsame properties; whereas in benzine or gasoline 
there are unavoidable losses to be sustained, particularly the 
valuable, very volatile parts, so that with a continued use of 
benzine the remaining less valuable ingredients, the heavier 
oils, must finally be enriched by important additions of fresh 
benzine or gasoline. 

An apparatus already installed for the recovery of the 
solvents does not need to be remodeled for the recovery of 
Carbon Tetrachloride, and distillation process may be like- 
wise carried through in the customary manner. Carbon Te- 
trachloride does not in the least affect the colors of fabrics. 
The most delicate colors, even aniline colors of silk, satin, laces, 



230 SOLVENTS FOR RUBBER. 

etc., are not affected in the slightest degree. A mixture con- 
sisting of equal parts of turpentine and Carbon Tetrachloride 
cannot be ignited at ordinary temperatures. A mixture of 60 
per cent. Carbon Tetrachloride and 40 per cent, naphtha is like- 
wise non-inflammable at ordinary temperatures. 

Chloride of Carbon. — This is obtained by the distilling 
of bisulphide of carbon into a vessel containing pentachloride 
of antimony, the product being rectified by distilling with 
lime. According to Simpson, this makes a good solvent for 
India-rubber and in a measure vulcanizes it. Newton also used 
a Chloride of Carbon in dissolving both India-rubber and Gutta- 
percha, while Crump used Tetrachloride of Carbon (which see). 

Chloroform is prepared generally by distilling together a 
mixture of spirit — that is, grain alcohol — with bleaching pow- 
der and water. Its density is from 1.496 to 1.498. It is one 
of the best rubber solvents known. It is costly, however, 
and has a bad effect upon workmen. Lascelles-Scott men- 
tions what he calls the A. C. E. mixture, composed of 
alcohol 15 parts, Chloroform 38 parts, and ether 47 parts, 
which yields a powerful solvent for India-rubber or Gutta- 
percha. Chloroform dissolves not only India-rubber, but fats, 
resins, sulphur, alkaloids, and many other organic compounds. 
It should be remembered that a small percentage of Chloroform 
in the air, even as little as 5 per cent., is dangerous to the 
workmen. Chloroform is used as the solvent for India-rubber 
which is treated with the ammoniac gas process for bleaching. 
Is also used alone, and in connection with naphtha for rubber 
cements, which are intended to adhere to glass. In the bleach- 
ing of Gutta-percha, it is also used as a solvent. One of the 
first uses of Chloroform in connection with India-rubber is to 
be noted under an American patent granted to Charles F. 
Durant, who announced the discovery of a solvent known as 
"perchloride of formyle, otherwise known as Chloroform." 

Creosote Oils, in connection with ordinary solvents for 
India-rubber, are said to produce a cheap and effective solvent. 
Indeed, John Bagnol, manufacturer for Charles Macintosh & 
Co., patented their use as applied to India-rubber. (See 
Creosote.) 



CHUTE'S SOLVENT— HEPTANE. 231 

Chute's Rubber Resin Solvent. — This is a mixture of 
methyl acetate with either acetone or methyl acetone. Patented in 
the United States in 1907. 

DiCHLOR-ETHYLENE is a non-inflammablc, non-poisonous sol- 
vent, of German origin. It has a density of 1.269, with a boiling 
point of 83° C. or 181° F. 

Dippel's Oil (or Bone Naphtha). — A thick, viscid oil of 
brown color and very disagreeable odor, which on distillation 
may be obtained limpid and colorless. It is prepared by the 
destructible distillation of bones, leaving boneblack as a resi- 
duum. It was one of the early solvents used for India-rubber. 

Ether. — This was one of the early solvents used in connec- 
tion with India-rubber. It is sometimes called Sulphuric Ether, 
but erroneously. It is prepared usually by distilling a mixture 
of alcohol and sulphuric acid, washing the distillate, and recti- 
fying the product with quick lime or something of that kind. 
It is a colorless, very mobile liquid, with a not unpleasant 
smell, burning taste, and very volatile. Its specific gravity is 
0.7183. It is soluble in water i to 12. Commercial Ether boils 
at 96° F., and yields a dense vapor. It is very inflammable, 
and, when mixed with air or oxygen, gives rise to a dangerous 
explosive mixture. It is one of the best solvents known for 
oils and fats, and is also an excellent solvent for sulphur. For 
use in rubber work Ether should be free from water, but not 
absolutely pure, necessarily. It is little used to-day in rubber 
mills, except in some lines of very fine work. It has the ad- 
vantage of being absolutely free from the smells that many 
solvents have. A little is sometimes added to ordinary rubber 
solutions to make a complete solution of India-rubber in 
naphtha. There are also certain processes, expensive ones to 
be sure, for treating perished rubber with Ether vapor to 
recover it. Ether was used to remove sulphur from vulcanized 
India-rubber waste in Newton's camphene process. 

Gasoline. — See Naphtha. 

Heptane. — One of the four isormeric hydrocarbons of the 
paraffine series, which occurs as a colorless liquid and is de- 
rived from heavy canned coal oil, petroleum, etc. Its specific 
gravity is 0.712. It is soluble in alcohol and in ether, and is 



232 SOLVENTS FOR RUBBER. 

used with paraffine wax and India-rubber in water-repellent 
compounds, 

IsoPRENE. — A body found in oil of caoutchouc. It boils at 
98.6° F., and possesses the property of absorbing quantities of 
oxygen when exposed to the air, in consequence of which it 
forms itself into an elastic spongy mass. This same volatile 
compound is obtained by the action of moderate heat on oil of 
turpentine. William A, Tilden, D.Sc, F.R.S., had some Iso- 
prene from turpentine placed in a bottle, his first result being 
a limpid, colorles liquid. After a time, this changed in appear- 
ance, looking like a dense syrup, on which floated several hard 
elastic masses. On examination, they turned out to be practi- 
cally India-rubber. This rubber united with sulphur in the 
same way as ordinary rubber, forming a tough, elastic com- 
pound. It was also soluble in benzine, etc. Dr. Weber, before 
the Society of Chemical Industry, reported on Tilden's dis- 
covery that Isoprene is so expensive that it cannot be converted 
into rubber without loss, and therefore the synthetical manu- 
fatcure of India-rubber, even if possible, was not probable. 

LiGROiN. — See Naphtha. 

Methane. — Professor Lascelles-Scott describes the manu- 
facture of what he calls Methane solvents, which are really 
benzines or benzols through which marsh gas has been passed. 
He claims that a benzine containing from 2 to 3 per cent, of 
Methane, obtained in this way, yields a better and more 
mobile solution than the ordinary solvent naphtha, and the 
solution when spread dries off better, besides giving a more 
finished surface. 

Naphthas. — The term Naphtha was originally applied to a 
variety of pungent, volatile, inflammable liquids that belonged 
chiefly to a class of ethers ; then it took in oils of natural origin, 
such as rock oil, petroleum oil, etc. ; at a later date, a light oil 
of coal tar, which should properly be designated benzol, was 
included under the name of Naphtha; while recently it has 
been extended so that it covers most of the inflammable liquids 
distilled dry from organic substances. It is applied in the 
United States to a series of hydrocarbons that are obtained 
from petroleum, whose boiling points vary with the densities, 



NAPHTHAS. 233 

from 65 to 300° F, The Naphthas of commerce are Bog-Head 
Naphtha, obtained from bog-head coal; Bone Naphtha, or Dip- 
pel's animal oil; Coal Naphtha, obtained from the distillation of 
coal tar; Wood Naphtha, or methyl alcohol obtained during the 
dry distillation of wood. Of these. Coal-tar Naphtha and Petro- 
leum Naphtha are most useful to rubber manufacturers. The 
former of these was used largely as a rubber solvent, but to- 
day it is almost wholly replaced by Petroleum Naphtha. The 
Naphtha which is derived from petroleum comes between 
gasoline, which is lighter, and benzine, which is heavier. 
Benzene is contained in the Naphtha produced by the destruc- 
tive distillation of coal, while benzine is a petroleum product. 
Benzine is really the first product that arises from the process 
of refining crude oil, and bears the same relation to Naphtha 
that the distillate does to refined oil, thus showing that ben- 
zine is simply a crude Naphtha. What is known as gasoline 
has a proof rate of 86° F., and boils at 90° to 100° F. Warm 
currents of air volatilize this type of Naphtha very rapidly, and 
its vapor unites with the atmosphere in explosive proportions. 

Coal-tar Naphtha was one of the first solvents used in 
rubber work. Macintosh, as far back as 1823, prepared it him- 
self for dissolving India-rubber for proofing. There is ob- 
tained from crude Coal-tar Naphtha what is known as "once 
run" Naphtha and "last runnings." The once run Naphtha 
is the starting point from which are derived the various grades 
of benzols, solvent Naphthas, etc., by fractional distillation. 
The specific gravity of solvent Naphtha should not exceed 
0.875. Its composition is a very complex affair, including 
xylols, cumols, homologous of benzol, together with some 
paraffine, and sometimes a little naphthaline. This last- 
named substance, by the way, is often objectionable, as it acts 
upon some rubbers like animal oil. Naphtha derives its vege- 
table solvent power largely from the xylol present in it. This 
is to-day removed and sold by itself as a solvent, though the 
residual Naphtha is simply robbed of that much virtue. 

Speaking of Naphthas, Lascelles-Scott, after exhaustive 
experiments, thus describes three used in England in rubber 
factories. Petroleum Naphtha in its solvent action on rubber 



234 SOLVENTS FOR RUBBER. 

showed slight action in the cold or under gentle heat. Viscid 
masses and semi-solutions were formed, but these solutions 
did not dry well. The same Naphtha had almost no solvent 
action on pitch. Shale Naphtha was useful only in dissolving 
Madagascar rubbers, and had no action on pitch, while Coal- 
tar Naphtha caused almost any rubber to swell quickly and, 
after gentle heat, to effect a good solution. It also readily 
dissolved pitch, forming a deep brown solution. 

The problem that confronts rubber manufacturers as a 
rule is the solution of gums that are more or less heavily com- 
pounded, which is an easier problem than the putting into 
solution of crude rubber that perhaps has not been broken 
down in any way. At the same time it is customary in many 
cases to apply a little heat during the mixing. The following 
table relates to Petroleum Naphthas. The C Naphtha has not 
only the greatest solvent power, but it is easier to evaporate 
after it has dissolved the rubber compound. B and A require 
a certain amount of heat to vaporize them : 

Specific Degrees Boiling 

Products. Gravity. Beaume. Points. 

Rhigolene 0.625 .. 65° F. 

Gasolene 0.665 85 120° F. 

C. Naphtha 0.706 70 180° F. 

B. Naphtha 0.724 67 220° F. 

A. Naphtha 0.742 65 300° F. 

Naphtha is more largely used in the proofing business 
than any other. It is, however, a general solvent for cements, 
and quantities of it are used in almost all lines of rubber work 
where there is any making up to be done of separate pieces 
after calendering. It is therefore necessary that a good grade 
be used when one considers the danger that may come from 
fires caused by the explosion or easy ignition of low grade 
solvents. Odorless Naphthas are those from which naphtha- 
line, a solid white body, has been removed, as it is the presence 
of this body that causes the strong smell. Naphtha treated 
by sulphuric acid is deodorized, acquiring a rather pleasant 
odor as a consequence. It is often mixed with other solvents 
— for example, with oil of turpentine — and is found thus to 
have a better effect on the rubber. 

Naphthaline (called also Anthracine). — Commercially 



NITRO BENZOL— OIL OF TURPENTINE. 235 

obtained from coal-tar, being among the third and fourth prod- 
ucts of the distillation of that body. Naphthaline is usually 
sold in rolls made by melting the large silvery plates or 
scales in which it crystallizes, and running the melted com- 
pound into molds. Its specific gravity is 1.15. It is insoluble 
in v^^ater and petroleum naphtha, but the liquids derived from 
coal tar dissolve it easily. Naphthaline is sparingly soluble in 
alcohol and ether, but readily in benzol. It is used in insula- 
ting paints, as when it evaporates it leaves a very solid film 
that is said to be absolutely free from porosity. 

NiTRO Benzol. — A compound obtained by boiling benzol 
with nitric acid. It is a brown, heavy, oily looking liquid, 
having a specific gravity of 1.2, a burning sweet taste, and a 
smell resembling that of oil of bitter almonds. It is used in 
the analysis of vulcanized India-rubber to dissolve the sub- 
stitute that may be incorporated in it. It is produced by the 
action of nitric acid and benzene, also called Nitro-Benzene. 
Used by Parkes in the manufacture of Parkesine. (See 
Acids and Alkalies ; also Naphtha.) 

Oil of Turpentine (crude) is what is known as an oleo 
resin, and is of about the consistency of fresh honey. There 
are more than a dozen varieties on the market, the more com- 
mon being Bordeaux, Venice, Canadian, and American. A 
fair quality of turpentine oil should begin to boil at 155° C. or 
312° F. The distillation of crude Oil of Turpentine by steam 
leaves ordinary resin. Oil of Turpentine is used in certain water- 
proof cements, in connection with both Gutta-percha and India- 
rubber. Where Oil of Turpentine is necessary for rubber work, it 
is well to have it free from the considerable percentage of water 
which it invariably contains. This is done by a treatment with sul- 
phuric acid, or by rectifying it over burnt lime. Turpentine, 
particularly that known as Venice Turpentine, is often used 
in connection with linseed oil and sulphur in the production 
of rubber substitutes. Professor Tilden showed, some years 
ago, that what appeared to be pure India-rubber could be 
obtained from turpentine ; indeed, he announced that he had 
produced it on a small scale. The same thing was also 
observed by Bouchardt. Venice Turpentine is obtained from 



236 SOLVENTS FOR RUBBER. 

Switzerland, where it is procured from the Larix Europea, or 
larch. The genuine Venice Turpentine is of the consistency 
of honey, cloudy, yellowish, or slightly greenish. It is entirely 
soluble in alcohol. The commercial Venice Turpentine is a 
factious substance, usually quite brown, and is prepared by 
dissolving rosin in Oil of Turpentine. Venice Turpentine is 
largely used in cements. Bordeaux Turpentine is the ordinary 
turpentine of commerce, getting its name from the port in 
France whence it is exported. (See Spirits of Turpentine.) 

Pentane. — A hydrocarbon of the paraffine or methane 
series. A colorless, volatile liquid which occurs in petroleum. 
Boiling point 98° F. Pentane is used with paraffine wax and 
India-rubber in water-repellent compounds. 

Petroleum. — A mixture of several hydrocarbons which, in 
fluid form, issue from the ground in many parts of the world ; 
also known as rock oil. It varies in consistency from a thin, 
light, colorless fluid with a specific gravity of about 0.750, to 
a substance as thick as butter, and almost as heavy as water. 
All kinds, however, have about the same constitution, consist- 
ing of carbon and hydrogen compounds only, and containing 
no oxygen. Asphalt and bitumen are closely allied to petro- 
leum. This oil is often used for restoring rubber that is 
oxidized somewhat, by immersion, and then hanging for a 
couple of days in a warm atmosphere. Petroleum is very 
rarely used in rubber manufacture, for although a good solvent, 
it weakens the goods exceedingly. Crude petroleum, however, 
is a valuable adjunct to the reclaiming of rubber, where, in 
the form of a cheap residuum, it assists in devulcanization and 
in sheeting. (See Naphtha.) 

Resin Oil. — This is obtained by subjecting rosin to dry dis- 
tillation, the specific gravity of the resultant oil ranging from 
0.96 to 0.99. It is rarely used as a solvent for rubber, in the 
ordinary meaning of the term. As a matter of fact, it is not a 
good solvent for crude rubber. For compounded rubbers, 
however, it works well and is often used, particularly in 
connection with pseudo guttas. In certain insulating experi- 
ments, where a thin sheet of Gutta-percha covered the con- 
ductor, and the outer Gutta-percha tube was full of Resin Oil, 



SHADE SPIRIT— TOLUENE. 237 

it gave, according to Professor D. E. Hughes, F.R.S., a higher 
insulation test than Gutta-percha alone. Professor Hughes 
used Resin Oil quite thick and viscid, and added resin and a 
solid residuum obtained from the distillation of palm oil. 
Resin oil in rubber compounding, however, softens the com- 
pound in a marked degree. (See Oils). 

Rhigolene. — See Naphtha. 

Shale Spirit is the solvent used in the Scottish waterproof- 
ing establishments. It is a product of the Scottish parafifine 
oil industry. 

Spirits of Turpentine is really oil of turpentine, and it has 
a specific gravity of 0.864. It is colorless, transparent, of a 
strong odor, and a bitter taste. It is insoluble in water, on 
which it floats, but readily soluble in strong grain alcohol, ether, 
and the fixed and essential oils. It is an excellent solvent for sul- 
phur, resin, and India-rubber. Spirits of Turpentine, with wood 
spirit alcohol, aniline, and nitric acid is used in surface work 
on vulcanized India-rubber. The earliest records of India- 
rubber speak of this oil as a solvent for it; indeed, the whole 
secret of rubber compounding for a number of years, even 
when the great Roxbury Rubber Co., of Boston, was running, 
was the solution of India-rubber in it. It is used in solutions 
that are expected to be sticky, and to dry slowly. 

Tetrachloride of Carbon. — See Carbon Tetrachloride. 

Tetrachlormethene Benzine Substitute is an excellent 
solvent, boiling at 75° C. Not easily ignited; of pleasant smell; 
made from chlorine and carbon bisulphide, 

Thion. — A substitute for bisulphide of carbon, manufac- 
tured in England, which is said to mix excellently with chloride 
of sulphur and is non-poisonous. 

Toluene. — That oil which is distilled from coal tar at a tem- 
perature of 230° to 234° F., also called methyl benzine and 
Toluol. It resembles benzene in outward appearance. Much 
commercial benzol contains Toluene, and this it is that makes it a 
far better solvent for rubber than benzine itself, as it dissolves the 
rubber in five-sixths of the time. The solutions are more mobile; 
it has a higher boiling point ; and, given a quantity of the solvent, 
will reduce more gum. It does not chill in cold weather, but keeps 



238 SOLVENTS FOR RUBBER. 

on macerating. It leaves a more solid deposit than does 
benzine, and does not induce headache or sickness among the 
workmen. 

VuLCOLEiNE is a liquid of English origin, and is put upon 
the market at about the same price as carbon bisulphide, and 
used for a solvent for India-rubber. It leaves on evaporation 
a perfectly tough and elastic film, quite unlike that left by coal 
tar naphtha, or the usual solvents. It mixes instantly with 
chloride of sulphur, and is intended to replace bisulphide of 
carbon in the cold curing process. It has no bad smell, nor is 
it unhealthful. 

Wood Spirit (also known as Pyroxylic Acid). — This is 
made from the destructive distillation of wood. Wood Spirit 
resembles grain or ethyl alcohol in its affinities, forming a 
series of compounds exactly corresponding to that of spirits 
of wine. Wood Spirit, when pure, is a thin, colorless Hquid, 
with a peculiar odor and a hot disagreeable taste. It boils at 
152° F., and its density is .798 at 60°. It mixes freely with 
water, and, like alcohol, dissolves resins and volatile oils, and 
is used as a cheap substitute for that purpose. Wood Spirit, 
also known as methylic alcohol, is not methylated spirit. It 
is not a solvent of rubber, but is used in many compounds that 
are intended as substitutes for vulcanized rubber. It is also 
used in dyeing India-rubber in connection with nitric acid, 
alcohol, and aniline. 

Xylol. — A colorless, somewhat aromatic, inflammable, oily 
liquid found in coal tar and wood tar; also called Xylene. (See 
Benzol.) 



CHAPTER XIIl. 

MISCELLANEOUS PROCESSES AND COMPOUNDS FOR USE IN THE 
RUBBER FACTORY. 

Many interesting formulas are given for the dyeing and 
surface coloring of rubber, although the processes are not 
such as will generally be used. A suggestion that comes from 
France is the dipping of rubber for an instant in a bath of 
nitric acid, then washing in water. For coloring, the rubber 
is dipped in an alcoholic solution of fuchsine. The experi- 
menter should appreciate fully, however, the effect that nitric 
acid produces on rubber, and govern himself accordingly. 

Alexander Parkes, who produced some exceedingly valu- 
able processes for the treatment of rubber, gives the following 
formulas for dyeing India-rubber: 

Black. — Boil from 15 to 30 minutes in a liquid prepared 
as follows : Sulphate copper, i pound ; water, i gallon ; caustic 
ammonia or muriate of ammonia, i pound. Or: Sulphate or 
bisulphate potash, i pound; sulphate copper, 12 pounds; water, 
I gallon. 

Green. — Muriate ammonia, 2 pounds; sulphate copper, i 
pound ; caustic lime, 4 pounds ; water, i gallon. Boil the 
rubber as before, 15 to 30 minutes. 

Purple. — Sulphate or bisulphate of potash, i pound; sul- 
phate of copper, ^ pound; sulphate of indigo, ^ pound. Boil 
the rubber, 15 to 30 minutes. 

Hoffer gives almost the same ingredients for producing 
these colors, adding the information that the articles are dyed 
by being boiled in these fluids from 15 to 30 minutes, the 
thicker the article the longer the boiling. This is done before 
the goods are vulcanized. 

Hard rubber may be decorated by means of pigments 
mixed with shellac and applied to the given surface with a 
brush. The surface then is to be pressed with some force 
against a hot plate of metal, whereby the colors are made to 
appear as though integral with the rubber. 

Wood coated a sheet of vulcanized rubber with chloride 

239 



240 MISCELLANEOUS PROCESSES. 

of silver, the idea being to use it in dental plates. Various 
processes have also been brought out for the surface treat- 
ment of rubber with gold leaf, bronzes, etc., usually applied 
in the form of powders, in the manner in which flock is applied. 
Truman also patented a process for electro-gilding rubber 
dental plates after they were finished. Goodyear dusted un- 
vulcanized rubber surfaces with plumbago or powdered metal, 
to make them conductive, pressed the dust in, and then 
electroplated it. 

The embossing of India-rubber surfaces has been practiced 
almost since the invention of the "triple compound," It is 
really nothing more than a light surface molding. This is 
done sometimes by embossing rolls, the rubber being cured 
after the impression is taken, and sometimes by being vulcan- 
ized on the impression plate. 

Bourbridge patented a process for embossing rubber by 
rolling it tightly on a drum with embossed paper or book- 
binders' cloth, and semi-curing it in that form, preferably by 
boiling at a temperature from 212° to 220° F. This boiling 
operation was not really vulcanization, but simply a means of 
setting the rubber which was afterward made up into goods 
and cured. 

In producing sheets of India-rubber for the manufacture 
of tobacco pouches, balls, balloons, etc., by this process, the 
sheet is calendered on sized cloth, partially vulcanized, printed, 
coated with transparent India-rubber, the goods made up, and 
the vulcanizing process completed. 

A great many beautiful colors are added to India-rubber 
surfaces by coating the sheet with a thin adhesive solution, 
dusting it over with colored flock, and then vulcanizing. By 
this process any color can be given to rubber surfaces which 
have a cloth-like appearance. 

Kelley produced a bronzed appearance on rubber coated 
fabrics by means of a roller partly immersed in a trough hold- 
ing the dye, curing either by dry heat, or by chloride of 
sulphur. His solution consisted of 2 ounces alcohol spirits, 
I ounce wood naphtha, 10 drops nitric acid, i ounce spirits of 
turpentine, with sufficient aniline dye to make the desired 



COLORED DESIGNS FOR FABRICS. 241 

color, 4 ounces liquid dyeing, 3 pounds rubber composition. 
He also impregnated farina with aniline solutions, dried it, and 
mixed it in the compound. 

In certain dyeing processes lakes are necessary. What is 
known as caoutchouc lake is made by steeping i ounce of Para 
rubber in a quart of light camphor oil, exposed to the sunlight 
for several days. This is said to be excellent for binding 
colors. 

Matthew's process for producing colored designs for 
proofed fabrics is to first coat the fabric in the ordinary man- 
ner with pure or colored India-rubber. When the design is 
to be printed on a black or dark ground, the last coating is 
mixed with starch or some powder that will render it non- 
adhesive, and to an extent absorptive. The fabric is then 
partially vulcanized, when the designs are printed on the 
desired surface, just as oil-cloth or linoleum is printed. The 
vulcanization is finished preferably by using chloride of 
sulphur. 

Colors suitable for admixture with rubber should answer 
the following requirements : They must be unaffected by water, 
by acids, by alkalies, and by chloride of sulphur. Further 
than this, they must not be affected by sulphur at temperatures 
ranging from 200° to 300° F. The colors must not be soluble 
in or affected by naphtha or other solvents used in rubber 
work. They must not be affected by heat up to 300° F. 
According to Frankenburg, his invention of aniline lakes 
answers all these requirements. His description is as follows : 

(A). Lakes prepared from acid aniline colors. — 'T have 
found that by converting any of the acids or suphonated aniline 
colors into compound lakes, such as barium-alumina, calcium- 
alumina, barium-chromium, or calcium-chromium lakes, colors 
are obtained answering all the above requirements, and 
therefore eminently suitable for the dyeing of India-rubber, 
waterproof, and other articles. The aniline dyes best suited 
for the production of these lakes are those known as azo or 
di-azo colors. From colors of this description I prepare lakes 
in the following manner : 50 pounds of orange II., or any other 
suitable azo or di-azo color, and 112 pounds of soda crystals 



242 MISCELLANEOUS PROCESSES. 

are dissolved in loo gallons of water at 170° F. This solution 
is then precipated with a solution of 150 pounds of barium 
chloride. The precipitate is kept boiling for half an hour. It 
is then left to stand, and washed several times with fresh 
water. Eventually a solution of 40 pounds of alumina sulphate 
is added very gradually, when a bright, fast, and flocculent 
lake is obtained, which, after filtration, drying, and pulverizing, 
is ready for incorporation with the India-rubber dough. It is 
evident that a great many variations of the process may be 
devised, but in every case the important point is the conversion 
of the aniline dye into one of the above-mentioned compound 
lakes. As regards the proportions given above, they are, of 
course, subject to such variations as are in accordance with the 
molecular weights and the commercial purity of the materials 
used, as well as with the particular properties and qualities to 
be imparted to the lakes for the purpose they are intended to 
serve. Using in this manner the numerous azo and di-azo 
dyes a very great variety of lakes may be produced, compris- 
ing all conceivable shades, and all suitable for the dyeing of 
India-rubber articles of every description. The lakes prepared 
from the acid oxy-ketone dyes and most of the natural dyes 
are very little suitable for this purpose, owing to their indiffer- 
ent and dull shades." 

(B). Lakes prepared from basic coloring matters. — "A 
large number of lakes derived from this class of dyes are also 
suited for the dyeing of India-rubber articles, although many 
of them are lacking in fastness to light acids and alkalies. 
To produce a perfect compound lake from these dyes tannic- 
acid and antimony, along with aluminum and barium, are used 
for the complete fixation and precipitation of these lakes. The 
following proportions give good results: Soda carbonate, 128 
pounds; barium chloride, no pounds; thioflavine, 25 pounds; 
tannic acid, 20 pounds ; acetate of soda, 20 pounds ; sulphate 
of alumina, 100 pounds. These colors can be made faster by 
adding to them a small quantity of antimony potassio-tartrate. 
The proportions of tannic acid, sodium acetate, and tartar 
emetic used in this process vary considerably with the differ- 
ent basic colors, such variations being due to the difference in 



THE CRAVENETTE PROCESS. 243 

the atomic weights and commercial purity of the basic 
dyes." 

Hebblewaite and Holt's process for producing designs on 
gossamer cloth calls for the spreading over the rubber surface 
of farina or other powder, then running the fabric through 
embossed rollers and producing patterns thereon. 

Mosley's ornamented fabric was a gossamer cloth covered 
with farina, the surface being printed much as calico is, and 
then vulcanized with chloride of sulphur. The colors were 
mixed with suitable solvents and a certain amount of paraffine 
or India-rubber added. A part of this invention was also the 
use of an engraved roller, which revolved in the vulcanizing 
solution, and came in contact with the surface of the rubber, 
only at its raised portion. Directly after passing over _ the 
roller, if the surface of the rubber were dusted with farina, it 
would adhere to the portions that had come in contact with the 
roller, and not to the rest, thus producing a design on the fabric. 
The whole of the coating was afterwards cured by vapor. 

Impregnating Rubber. — Lessnenn and Weinkopf advise the 
following : Sixty per cent, birch tar oil ; 38 per cent, coal tar 
benzine ; 2 per cent, dissolved dextrine, to prevent sun-crack- 
ing. Apply with brush. 

SHOWER-PROOF PROCESSES. 

The Cravenette and other processes for rendering textile 
fabrics waterproof or water-repellent have attracted so much 
attention in the rubber trade that space will be given here to 
a description of the Wiley patent, which is used at the Craven- 
ette Works, Bradford, England. To begin, the waterproofing 
compound is applied in a solid or hard state by the action of 
friction and heating. In other words, there are no solvents 
used, nor is it a calendering process. The advantage of this is 
a lessening in the cost of applying waterproofing solutions and 
a further valuable result is that the dyes on various fabrics 
are in no way disturbed, and no unpleasant odor is developed 
or imparted to the cloth. The substances chosen are those 
which have a low melting point, so that the fabrics are not 
damaged by heat. They are preferably ozocerite, stearine. 



244 MISCELLANEOUS PROCESSES. 

spermaceti, paraffine wax, beeswax, or Japanese wax. These 
are sometimes used singly, and sometimes in combination, 
considerable judgment being necessary in selecting those 
which have an affinity for or are readily absorbed by the fibers 
of particular fabrics, influenced also by the nature and color of 
the fabric. In some cases India-rubber, Gutta-percha, maltha, 
asphaltum, resin, and artificial gums are found valuable in 
small proportions, and in conjunction with the substances 
already mentioned. 

In order to apply the waterproofing substance, it is 
formed into slabs. The fabric is carried on a reel supported in 
bearings between suitable frames, at the opposite end of which 
is a hollow cylinder mounted upon carrying rollers and sup- 
ported laterally by side rollers. This cylinder is filled with 
water. The slab of the compound, wider than the fabric to 
be coated, is fixed in a holder above the cylinder. This holder 
is so arranged that the weight presses the slab against the 
cylinder. The fabric is then drawn from the reel over and 
under tension bars, under a supporting roller, between it and 
the rubber cylinder, and around the cylinder and under the 
slab, then over the guide roller and into a drying machine. 
The friction of the cloth wears the slab away and uniformly 
deposits it upon the cloth, while in the drying machine, the 
heat melts the waterproofing compound, and it is absorbed by the 
fibers which are thereby rendered waterproof or water-repellent. 

Other formulas for shower-proofing and waterproofing are 
of interest in this connection and a few are given : 

The first is a German waterproofing compound : Alum, lo 
pounds ; sugar of lead, lo pounds. Dissolve in hot water and 
allow the precipitate to settle. Dilute the clear liquid with 
I20 gallons water and add 2 pounds isinglass in solution. The 
goods are steeped in this solution 8 or 10 hours. 

An American shower-proof compound: Liquid silicate of 
soda or liquor or flint, i gallon ; white oxide of zinc, i pound, 
if the fabric is to be colored, add coloring matters. The 
mixture may be applied to fabrics hot or cold, by means of a 
brush or by immersion of the fabrics, which are afterwards to 
be run between rollers. 



SHOWER-PROOF COMPOUNDS. 245 

Another American compound: Dissolve separately, i:^ 
pounds alum (in hot water), 10 ounces acetate of lead (in hot 
water), and i^ pounds carbonate of magnesia (in hot water). 
They should aggregate about 31 quarts. Add the acetate of 
lead to the alum solution, and then the carbonate of magnesia ; 
after which 10 quarts liquid as above and i tablespoon white 
gum arabic. Stir ^ hour; let stand 24 hours, skimming now 
and then ; in 48 hours the first mixture will be ready. Lay the 
fabric in a vessel and pour liquid over it, beating the fabric 
well and removing it within an hour. 

A third American shower-proof compound: 

A. Carbonate of soda 16 parts. 

Lime 8 parts. 

Water 32 parts. 

Boil 30 minutes, let settle and pour off the clear lye. 

B. Glue or gelatine 3 parts. 

Linseed oil 3 parts. 

Add after soaking glue in cold water 12 hours. 

C. Tallow (or other animal fat) 16 parts. 

Rosin 8 parts. 

Melt together. 

To (A) boiling hot add hot (C), then pour in (B) and stir hot until well 
mixed. 

D. Sulphate of alumina i pound. 

Acetete of lead i pound. 

Boiling water 8 gallons. 

Let settle and draw off clear liquor for use. To i gallon water add i 
ounce of first product for bath for cotton goods. Add i ounce for silk 
or wool. Immerse 24 hours or more, then six hours or more in second 
compound (D). 

Proofing compound: 

Mixture i. — Dissolve in water, 50 parts alum; also dis- 
solve in water, 35 parts sugar of lead ; mix. 

Mixture 2. — Combine 17 parts paraffine and 35 parts ben- 
zine; drop into this 17 parts Caoutchouc. Stir until well dis- 
solved. 

Mixture 3. — To the clear decanted liquor from the above 
mixtures, add 8 parts alcohol and 4 parts eau de cologne (or 
oil of lemon). 

An English compound for waterproofing textile fabrics : 
Sugar soap, i pound ; water, 16 gallons. Soak articles in them 
for 6 hours ; drain, but do not wring them ; and place them in 
the following solution: 



246 MISCELLANEOUS PROCESSES. 

Alum, I pound; water, i6 gallons; soak again 6 hours, 
take out and dry without wringing. 

Another English compound for waterproofing textile 
fabrics : Concentrated size, 8 pounds ; aluminum sulphate, 5 
pounds ; barium chloride, 6 pounds ; water, 16 gallons. After 
coating, varnish with the following: Melt together 22 pounds 
colophony, 4 3-5 pounds crystallized soda, and 11 pounds 
water. Then add : Ammoniacal fluid, 5^ pounds ; and water, 55 
pounds ; or : Borax, 6 pounds ; shellac, 6 pounds ; and water, 
40 pounds. 

A German compound for waterproofing woolens: Dissolve 
100 pounds alum in moderate quantity of boiling water; soak 100 
pounds glue till it has taken up twice its weight of cold water, 
then apply heat to dissolve it ; stir 5 pounds tannin and 2 pounds 
soluble glass well into the glue, then add the alum solution. Enter 
the goods at 80° C, and steep 30 minutes. Take out and drain 
several hours, stretch on a frame, and, when dry, calender. 

A German shower-proof compound: Stir 9 pounds casein 
well in 32 quarts water, adding little by little 25 pounds of slaked 
lime. Add a solution of 4^ pounds soap in 26 quarts water. 

Filter and treat the cloth with the liquid. Dress with a 
dressing of acetate of alumina, by which the casein is rendered 
insoluble in the fibers of the cloth. After two applications, rinse 
the goods with hot water, press strongly, and dry. 

One process for waterproofing threads and yarns used in 
weaving ducks and other fabrics is in two parts, the first of which 
relates to a tanning mixture in which the yarns are immersed, 
consisting of: Birch bark, 14 pounds; bichromate of potash, i 
pound; chloride of calcium, ^ pound; tar i pint; solution of 
alkali, 2 pounds. The threads are first boiled in a 5 per cent, 
solution of alkali to destroy perishable matter, after which they 
are immersed in the tanning liquid and dried. The second part 
consists of preparing or dressing the threads with the following 
compound : 

Poppyseed oil, 2 gallons; India-rubber solution, 2 pounds; 
red oxide of mercury, i pound; resin, 28 pounds; beeswax, 28 
pounds; palm oil, 14 pounds. The threads after this treatment 
are wound on reels for weaving. 



WATERPROOF FABRICS. 24% 

Forster, as far back as 1847, made a water-repellent comr. 
pound in which he used spermaceti, wax, and stearine, while three 
years prior to that Townsend used two solutions to accomplish 
that end, the first being water, calcined British gum, white soap, 
logwood liquor, and rock alum ; the second being water, sulphate 
of zinc, calcined British gum, and palm soap. 

The Kyanized cloth process is well known in connection with 
preserving fabrics, the treatment being with a mixture of cor- 
rosive sublimate, chloride of zinc, pyrolignite of iron, oil of tar, 
and resinous matters. Fabrics treated in this way have been used 
for the manufacture of hose. 

Crape cloth is a fabric which has much the appearance of real 
crape, but is far less expensive. It is treated with processes 
similar to the Cravenette process, which make it both waterproof 
and durable. Two patents for this process have been granted to 
W. E. B. Priestly. 

According to Dr. Doremus the lightest fabrics are rendered 
uninflammable by dipping them in a solution of phosphate of 
alumina in water. 

Allard's fireproof felt is made of 50 per cent, of asbestos and 
50 per cent, of animal hair, and for ordinary purposes is wholly 
fireproof. 

Canvas for sails and other purposes, which it is desired to 
render waterproof, is treated by the Dumas process so that, while 
it is both waterproof and fireproof, it is still elastic and permeable 
by air. The treatment is this: The material is first put in a 
solution of gelatine, then run through pressure rollers, and spread 
in the open air to dry ; later it is dipped in a cold solution of alum 
again exposed to the air, then washed in cold water, and finally 
dried. 

Frankenburg's waterproof cloth is made in this manner: 
Both warp and woof are coated in the yarn with India-rubber, 
then powdered with farina, then woven, after which the fabric 
is calendered, and the result is a cloth that it thoroughly water- 
proof, and yet does not give evidence of having rubber in its 
make-up. 

Smith's porous waterproof fabric called for a compound 
made of 100 parts of paraifine melted by heat, to which was 



248 MISCELLANEOUS PROCESSES. 

added 15 per cent, of India-rubber, the mixture being kept from 5 
to 30 minutes at a temperature of 100° C. The solution, either 
as it is, or with a solvent, is then transferred to the cloth by means 
of a set of rollers which have a temperature of about 70° C. 

Amphiboline. — A natural earth found in Germany, which 
once mixed with water, will not mix again. Used with a small 
amount of gelatine for waterproofing. 

Cohuru's waterproofing compound. This consists of crude 
petroleum, 3 quarts; liquid asphalt, i pint; white drier, i pint; 
beeswax, 4 ounces, and gum-arabic. 

DEODORIZATION. 

The odors that cling to vulcanized rubber goods and to 
Gutta-percha are often very objectionable, and the following 
processes are given for deodorization : 

Cattell's process: For every pound of well cleaned Gutta- 
percha take 15 pounds of the following solution: Benzol, i 
gallon; alcohol, i ounce; glycerine, 30 drops. Or: Benzole, i 
gallon; nitrate of the oxide of ethyl, 30 drops; heat in a closed 
vessel to 110° F. The Gutta-percha is recovered by cooling to 
below 32° F., and pressing or by distilling off the solvent, or by 
precipitation with fusil oil. 

Freeley's process : Dip vulcanized rubber goods in a solution 
of : Salicylic acid, 20 grains ; alcohol, ^ pint. This will deodorize 
them, but goods will be toughened and the deodorization in- 
creased by subjecting goods to a bath in hot or cold solution 
composed as follows : 

(A) Bark of oak, 50 pounds; bark of hemlock, 50 pounds; 
bark of sumac, 50 pounds ; water, 900 gallons. 

(B) Solution as above, 2 gallons; salicylic acid, 20 grains; 
large tablespoonful of Russian Jackten extract, dissolved in 2 
pints of alcohol, i pint of ether, and 10 grains of salicylic acid. 

Bourne's process : The articles to be deodorized are placed 
between layers of charcoal and heated from 120° to 150° F., if 
unvulcanized ; 180° F., if partially vulcanized; or 212° F., if com- 
pletely vulcanized. Heat for six hours or more. 

Lavater and Tranter's process: Subject the articles to a 
boiling in potash, then to a vacuum, then to a pressure of air 



PRESERVATIVE PROCESSES. 249 

scented with some essence. They claim the extraction of the sul- 
phur from the pores of the rubber in the form of sulphureted 
hydrogen and its replacement by perfumed air. 

Charles Hancock's process: To remove the odor of Gutta- 
percha, steep it in the following solutions : 

(A) Soda or potash, i pound; water, 10 gallons. 

(B) Chloride lime, i pound; water, 10 gallons. 
De la Granja's process: 

Iodine 15 grains. 

Permanganate of potassa 20 grains. 

Iodide of potassium 60 grains. 

Glycerine , . 4 ounces. 

Sulphite of soda 4 ounces. 

Sulphite of lime 4 ounces. 

Sulphite of potassa 4 ounces. 

Water li to 2 gallons. 

Steep or macerate rubber in a solution composed as above, 
in a close earthern vessel, 24 hours, the solution being cold. 
Then heat the solution gradually to boiling point and uncover the 
vessel until -| of weight of solution evaporates. When the solu- 
tion cools remove the rubber. 

The Traun Rubber Co. patented a process for adding pow- 
dered perfumes to India-rubber, the stock being used for dental 
dam, dress shields, and the like. 

PRESERVING RUBBER GOODS. 

The deterioration of vulcanized rubber goods is often a 
serious matter, where it is necessary for some time to keep them in 
store. Wherever possible, they should be kept in a cool dark 
place, and away from warm currents of dry air. It has been 
advised that such goods as druggists' sundries be stored in an air- 
tight receptacle in the bottom of which is placed a vessel contain- 
ing benzine, which is allowed to evaporate slowly. Kreusler and 
Bude in Der Techniker recommend the dipping of the articles in 
a paraffine bath, heated to about 212° F. This does not injure the 
color or the appearance, but is said to enable the goods to effectu- 
ally resist both light and atmospheric influences. From its well 
known softening effect on India-rubber, however, paraffine is 
likely to be used with considerable care by rubber manufacturers. 
In the line of mechanical goods. Turner patented a process for 



250 MISCELLANEOUS PROCESSES. 

treating both hose and tubing with carbolic acid, either during its 
manufacture or after vulcanization in order to preserve it, Tor- 
rey also saturated duck with carbolic acid before it was made up 
into hose, 

Mowbray's process for preserving rubber in valves: The 
use of 20 pounds of India-rubber, washed and cut fine, in con- 
nection with 5 to lo pounds of naphthaline ; digest 24 to 48 hours, 
at 180° to 230° F, Masticate in a machine heated to 212° F., 
until it forms a plastic homogeneous compound. If other sub- 
stances are to be added, treat as follows : 

1. Soluble matters (sulphur, antimony, resins, etc.) dissolve 
in naphthaline, melted or boiling, and add to above naphthalized 
caoutchouc at temperature of 240° F. 

2. Materials insoluble in naphthaline (oxides of lead and 
zinCj chalk, etc.) deprive of moisture and heat to 212° F. and add 
to naphthalized caoutchouc. 

This compound can be used for soft or hard rubber, accord- 
ing to the proportion of sulphur used. The object is to preserve 
the elasticity of rubber and prolong its durability, 

Trueman's process for preserving India-rubber, and fibers 
that may be used with it, employs the peroxides of manganese and 
lead and the black oxide of copper, all of which have the property 
of decomposing ozone in great quantity, and converting it into 
oxygen. The inventor believes that ozone is the active agent in 
producing decay, and, by changing it into oxygen, he arrests such 
decay. In applying these oxides, he mixes them with ozocerite 
or tar, 

Elworthy patented a process for storing rubber goods in a 
receptacle filled with nitrogen, hydrogen, marsh gas, or carbonic 
acid gas. This was recommended especially for rubber goods in 
India. 

Benton (American patent) describes the following: A com- 
position for preserving India-rubber, consisting of one part tur- 
pentine as much camphor gum as the turpentine will readily dis- 
solve, and one part linseed oil proportioned to the combined part 
of turpentine and camphor gum. 

Truss (English patent) advises: A mixture of 95 parts of 
soda-ash and 5 parts of commercial carbonate of ammonia is 



FASTENING RUBBER TO METALS. 251 

dissolved in hot water and applied to India-rubber articles to 
preserve or restore them. 

Zingler's process treats decayed rubber goods by long solu- 
tion in boiling water containing tartar emetic ; mixed afterwards 
with tannic acid and calcium sulphite. 

FASTENING RUBBER TO METALS. 

The problem often comes to rubber manufacturers as to how 
to stick rubber or rubber compounds to iron so that they will not 
part from it, no matter under what strain. This is done success- 
fully by a number of different formulas. Where the processes 
are skilfully carried out, the rubber should adhere so firmly to the 
iron, that it will disintegrate and give way anywhere else in the 
mass, except where its surface is in contact with metal. The 
basis of all these processes is said to be the chemical affinity for 
sulphur which is in the rubber with the copper salts used in the 
compound. One formula for this is : First, the grinding of the 
iron, finishing it with a file, and dipping it in strong lye to remove 
all grease, and afterward in muriatic acid or dilute sulphuric 
acid heated in water. The metal is cemented before the rubber 
is applied. 

The process patented by Garrity and Avery, is as follows: 
Nitric acid (41° Beaume), 10 gallons; muriatic acid (22° 
Beaume), 10 gallons; mix and add pure tin, finely divided, 10 
pounds. 

Immerse the iron for 8 seconds, remove and dip into weak 
solution sulphuric acid, then wipe with a woolen cloth. Then 
apply with brush or otherwise, the following compound : Rubber 
cement 7^ gallons; litharge, 6 pounds; and sulphur, 3 pounds. 
Add vulcanizable rubber compound at once, and vulcanize. 

Hall's process : Water, 100 quarts ; caustic potash, 10 pounds ; 
cyanide of potash, 2 pounds ; sulphate of copper, 2 pounds ; sul- 
phate of zinc, 2 pounds. The pickle and bath are made of water 
and about 10 per cent, sulphuric acid, the tub being lined with 
brass plate. 

Adam's process: A weak solution of sulphate of copper is 
made — say 2 or 3 ounces of the crystallized salt to the gallon — 
and this solution may be acidulated with sulphuric acid — say 



252 MISCELLANEOUS PROCESSES. 

about ^ gill of strong acid to the gallon. For a fine film for 
"dipping" articles of iron, steel, or tin, to which the rubber com- 
pound is to be applied, if the metal is copper, it should first be 
coated with tin, nickel, or iron. 

The shellac process calls for a cement made of shellac steeped 
in ten times its weight of concentrated ammonia, the solution 
being allowed to stand three or four weeks. This solution is 
painted on the iron, allowed to dry, and the rubber vulcanized 
upon it. 

THE USE OF GASES. 

Before India-rubber reached its present value in the arts, 
and before coal gas was generally known as an illuminant, Mol- 
lerat obtained oil of caoutchouc by distillation and made a fine 
quality of illuminating gas from it. It is needless to say that the 
process is not practiced to-day. 

Pellen rendered India-rubber impervious to gas by coating 
it with collodion mixed with a very small quantity of castor oil 
or with a varnish composed (i) of 32 per cent, of gum arable, 
8 per cent, of sugar, and 60 per cent, of water, or (2) made from 
28 per cent, of dextrin, 60 per cent, of water, and 12 per cent, of 
gelatine. 

Bousfield rendered vulcanized India-rubber impermeable to 
gas by applying linseed oil to it in the form of a varnish, the 
articles being heated. 

Parkes suspended articles to be vulcanized in a dry heater 
and passed the following gases into the chamber as a means of 
vulcanization : Sulphurous acid, gas, chlorine, nitrous acid, or the 
vapors of bromine or iodine. 

Charles Hancock cured rubber by the action of vapors pro- 
duced by dissolving zinc, copper, or mercury in nitric acid. The 
action of these vapors being so solvent, only one or two moments 
were given, and the surfaces then washed in an alkaline solution. 

Nickels passed sulphur fumes and hydrogen into the gum 
while in a masticator, curing afterward by heat. 

Johnson prepared carburet of hydrogen from oil of tar as a 
solvent for Gutta-percha. In order to overcome the smell of the 
solvent, he added a little alcohol in which was essence of lavender. 



METALS AND RUBBER. 253 

Hughes made an artificial rubber from gelatine, resin, oil, and 
tannin, improving the compound by exposing the compound to 
the action of hydrogen, sulphurous gas, sulphureted hydrogen, 
nitrous gas, or ammonia. 

Brooman treated vulcanized waste rubber with vapors of tur- 
pentine in his reclaiming process. 

Lake bleached India-rubber in a stream of ammonia gas or 
chloride of ammonia, afterwards thoroughly washing the gum in 
hot water. 

A great many rubber goods — ^that is, thin sheet goods — are 
cured by what is known as the vapor process. This is done in 
many cases by hanging the goods in an air-tight chamber, like a 
dry heater, and passing the vapor, which is either that of chloride 
of sulphur alone, or chloride of sulphur mixed with carbon bisul- 
phide, into the curing room. Small articles are often put in a 
tumbling barrel made of wire, which revolves slowly in the vul- 
canizing room, thus giving the vapor a chance to do its work 
thoroughly. The rubber surfaces are of course dusted first, to 
keep them from adhering. Proofed cloth is cured in vapor by 
passing the rubber surface over troughs in which this reagent is 
slowly evaporating. 

The vapors of ozocerite are also used in rendering cloth 
water-repellent. 

Vulcanized India-rubber, whether compounded or pure, is 
permeable by gas. In making flexible gas tubing, therefore, it 
must be coated or in some way protected in order to make it gas 
tight. The common way of accomplishing this is to cover the 
rubber tube with an outer tube made of glue, glycerine, and 
bichromate of potash, this covering being protected in turn by a 
woven fabric. Another plan for accomplishing the same result 
is to have an outer and inner tube of India-rubber, between the 
two being vulcanized a sheet of tin-foil. 

ACTION OF METALS ON RUBBER. 

The action of various metals on India-rubber has always 
interested rubber manuftcturers. In the memoirs and proceed- 
ings of the Manchester (England) Literary and Philosophical 
Society 1890-91, William Thomson, F.R.C., and Frederick 



254 MISCELLANEOUS PROCESSES. 

Lewis published an exceedingly interesting paper on this subject. 
They covered almost all of the metals that are likely in any way 
to come in contact with rubber surfaces, and proved what has 
long been acknowledged by rubber manufacturers, that the action 
of copper is most harmful. The metals that have no action at all 
on rubber are gold, silver, bismuth, antimony, arsenic, tin, chro- 
mium, iron, nickel, cobalt, zinc, and cadmium. Those that act 
only in a slight degree on rubber are lead, aluminum, palladium, 
and platinum. 

Of the salts of metals that are very destructive, copper stands 
first, manganese oxides and nitrate of silver, being, however, 
almost as bad. Several other nitrates have also an injurious 
effect, although not as much so as those just mentioned. They 
are the nitrates of ammonia, uranium, sodium, and iron. 

According to N. Foden, a well-known English expert, 
proofed goods in browns have caused him more trouble by 
deterioration than any other colors — more than black, even — and 
it is to be said right here that blacks as a rule are viewed with 
distrust by manufacturers, because it is believed generally that 
copper salts are used in the dyeing. Mr. Foden instances the 
time when brown tweeds were used largely, and when most man- 
tifacturers experienced a great deal of trouble with them, as the 
browns showed early signs of decay, while the grays remained 
soft and flexible. Mr, Foden suggests that, as certain dyers use 
lime, which is cheaper than logwood, this may act destructively 
upon the rubber. 

ARTIFICIAL RUBBER MILK. 

When rubber in solution of almost any of the ordinary sol- 
vents is mixed with a moderately large quantity of methylated 
spirit, it is precipitated and forms later a sticky, whitish mass 
from which the resins and coloring matter have been taken by the 
spirit. Instead of this process, Lascelles-Scott advises the fol- 
lowing: Take a lo or 15 per cent, solution of fine Para rubber in 
benzine or chloroform with a little strong alcohol, but not enough 
to precipitate the rubber. If a considerable volume of tepid water 
be then quickly stirred into the solution, the rubber slowly 
separates from its solvent. If to this be added a little resin-potassa 



RUBBER SPONGE. 255 

soap, with a little liquor ammonia, the emulsion is very similar 
to rubber milk. The distinguished author suggests the use of 
potassa soap made of the native rubber resin as the best emulsi- 
fying compound for such a purpose. 

In writing on the preservation of genuine rubber milk, he 
also condemns the use of creosote, for, although it prevents fer- 
mentation, it does not hinder the gum from separating. He ad- 
vises the use of ammonia and if it is to be kept through hot 
weather, the addition of a fragment of camphor or naphthaline or 
a few drops of santal-wood oil. 

Thermophoric Mixture. — Tiemar (Germany), patents the 
following: A thermophoric mixture comprising thermophoric 
salt, dissolved sunflower seed, Greek hay-seed (Faenum Grae- 
cum) or similar vegetable-seeds which contain viscous substances 
and a fat which will not affect India-rubber and the like material. 

Zieger and Weigand (British patent) cover a process for 
exposing dipped goods, after each dipping, to air-dried bi-calcium 
chloride or by cooling. 

Rendering vulcanized rubber adhesive. — Raymond's patent 
consists of treating India-rubber with benzine or a substance 
having an analogous action thereupon, then immersing the rub- 
ber in a solution of permanganate of potassium and a suitable 
acid, and again treating the rubber with benzine or a substance 
having similar action thereon. 

Rubber Sponge. — The Harburg- Vienna Rubber Co. patent 
the following: Unvulcanized India-rubber is mixed with natural 
seeds, or with molded bodies of flour, clay, gelatine, sugar com- 
positions, or other substances, or with non volatile soluble metallic 
salts, either by rolling, or by first dissolving the India-rubber in 
a hydrocarbon. The mixture is vulcanized, and the added bodies 
are subsequently washed out with water, acids, or alkalies. 

Refining Gutta-like Gums. — Willmowski's patent consists in 
dissolving the gum in hot petroleum naphtha, removing the in- 
soluble parts, cooling the solution until the gum itself is pre- 
cipitated while the resins remain in solution. Then washing the 
precipitated gum in cold petroleum naphtha, which removes 
soluble parts, and then evaporating the naphtha from the remain- 
ing purified gum. 



256 SHRINKAGE OF RUBBER. 

Crude Rubber Purifying— British patents of Thame and 
the South Western Rubber Co, — Rubber is first soaked in hot 
dilute caustic potash, and then immersed in a solvent. When 
partially in solution the tank is filled with water. After 1 8 to 24 
hours the liquid is removed and the rubber washed with boiling 
water. 

Banana Rubber Process, — Bananas are washed and cut cross- 
wise, and the liquid extracted in a centrifugal machine. The India- 
rubber separates from the liquid on standing. British patent by 
Zurcher, of Jamaica, West Indies. 

SHRINKAGE OF RUBBER. 

The following table shows the average rate of shrinkage in 
the various leading grades of India-rubber, and also the widest 
range of shrinkage noted in the practice of some extensive manu- 
facturers. The figures express percentages in weight : 

Average Range 

Para sorts : 

Fine 16 to 18 15 to 20 

Medium 17 to 19 16 to 22 

Coarse 22 to 28 18 to 35 

Mangabeira 25 to 30 20 to 35 

Caucho 26 to 34 20 to 40 

Centrals 26 to 32 20 to 40 

Africans : 

Tongues 19 to 24 18 to 25 

Flakes 28 to 33 25 to 35 

Thimbles 22 to 28 15 to 35 

Accra sorts 24 to 32 20 to 40 

Congo sorts 19 to 24 18 to 35 

Benguela sorts 16 to 20 16 to 20 

Mozambique sorts 17 to 28 10 to 35 

Madagascar sorts 30 to 40 25 to 55 

Assam 23 to 31 8 to 45 

Borneo 33 to 38 30 to 45 

Mr. T. Bolas, in his "Cantor lectures" on India-rubber, in 
1880, gave the following estimates of shrinkage of these leading 
grades : 

Para 15 per cent. 

Para negroheads 25 " 

Ceara 28 " 

Guayaquil 40 " 

Borneo 25 " 

African ball 25 " 

African tongues 35 " 

African niggers 25 " 

Madagascar 25 " 



SHRINKAGE OF RUBBER. 257 

PARA RUBBERS. 

The next table indicates in detail the percentage of shrink- 
ages in the various grades of Para rubber, also determined by the 
practice of American manufacturers : 

Fine Medium Coarse 

Bolivian 15 to 17 16 to 18 20 to 25 

Mollendo 15 to 17 16 to 18 

Madeira 15 to 18 16 to 19 20 to 25 

Manaos 16 to 17 17 to 18 18 to 22 

Upriver 16 to 18 17 to 19 18 to 25 

Matto Grosso 16 to 18 17 to 19 20 to 28 

Angostura 16 to 18 17 to 19 25 to 30 

Caviana 16 to 18 18 to 20 25 to 30 

Itaituba 17 to 18 18 to 19 20 to 25 

Islands 18 to 20 18 to 22 25 to 35 

Cameta 30 to 35 

The shrinkage of Mangabeira (Pernambuco) thin sheet is 
about 25 to 30 per cent. ; thick sheet, 30 to 35 ; ball, 20 to 25. 
Caucho (Peruvian) slab, 30 to 40; sheet, 30 to 35 ; strip, 25 to 35 ; 
ball, 20 to 25. 

The better grades of Centrals shrink from 25 to 30 per cent. ; 
other grades, generally from 30 to 40. 

AFRICANS. 

The Gold Coast sorts (including Accra, Cape Coast, Salt- 
pond, Addah, Quittah, and Axim) range about as follows : But- 
tons or biscuit, 20 to 30; flake, 30 to 35 ; lump, 30 to 40; niggers, 
20 to 35. 

Cameroon ball, 18 to 25 ; clusters, 18 to 28. 

Lagos buttons, 25 to 35; lump, 30 to 40; strip, 25 to 35. 

Congo buttons, 25 to 30; ball No. i, 20 to 25; ball No. 2, 
25 to 35 ; Upper Congo ball and strips, 20 to 35 ; red ball, 18 to 
22; Equateur small ball, 16 to 20; mixed ball, 18 to 22; Lopori 
small ball, 16 to 22 ; Kassai black twist, 18 to 22 ; red twist, 20 to 
25 ; ball, 20 to 25. 

Benguela (and Loanda) sausage, 16 to 20; niggers, 18 to 20, 

Mozambique (including Lamu) ball No. i, 10 to 15; ball 
No. 2, 15 to 25 ; ball No. 3, 25 to 35 ; sausage, 20 to 35. 

Madagascar pinky, 30 to 35; Majunga, 30 to 35 ; black, 30 
to 40 ; niggers, 30 to 40. 



258 SHRINKAGE OF RUBBER. 

EAST INDIAN. 

Assam No. i, lo to 15 ; No. 2, 20 to 30; No. 3, 30 to 35. 
Penang, No. i, and Java No. i, 10 to 15 per cent.; other 
numbers same shrinkage as Assam. 

E. Chapel gives this table of percentages of shrinkage: 

Para, fine 12 Ceara 28 

Para, coarse 25 African ball 28 

Loando 17 Madagascar 28 

Colombia 20 Assam 28 

Java 22 Gaboon 35 

Gambia 24 Borneo 35 

TO FIGURE SHRINKAGE IN CRUDE RUBBER, 

It is Strange that there should be a divergence of opinion 

and method in arriving at the net cost of rubber after washing, 

sheeting, and drying it, yet such is the case. To assist those who 

have not studied this question, the right and the wrong way of 

figuring on shrinkage is given here. Take, for instance, an 

average-priced rubber: 

Example A. 
100 lbs. rubber at $0.50 = $50.00 
20 lbs. shrinkage = 20 per cent., or i-5th. 

80 lbs., net cost $50.00, as above. 
80 ) 50.00 ( 62.50 
480 

200 
160 

400 
400 

Some persons, however, figure in this way: 

Example B. 

100 lbs. at $0.50 lb. 

Shrinkage 20 per cent. = i-5th. 

$0.50 4- i-5th (10 cents) = 60 cents. 

Example A. — Correct method — net cost $62.50 

Example B. — Incorrect method — ^net cost 60.00 

DiflFarence $2.50 

This is a diflference of 4 per cent., which, if it occur in manu- 
facturing a large amount of goods where rubber is the greater 
part of the compound, would make quite a difference in the profit. 



SPECIFIC GRAVITY. 259 

SPECIFIC GRAVITY OF RUBBER. 

The following records of the specific gravities of different 
samples of India-rubber have been collected : 

Best Para, taken in dilute alcohol (Ure) 0.941567 

Best Assam, taken in dilute alcohol (Ure) 0.942972 

Best Singapore, taken in dilute alcohol (Ure) 0.936650 

Best Penang, taken in dilute alcohol (Ure) 0.919178 

Caoutchouc (Julian) 0.920000 

Crude caoutchouc of India (Adriani) 0.966800 

Black caoutchouc (Adriani) 0.945200 

Prepared from juice in pure state (Faraday) 0.925000 

Determined by E. Soubeiran 0.935500 

Determined by Payen 0.925000 

H. L. Terry, F.I.C., gives the specific gravity of Para rub- 
ber and refers to Faraday's figures as being most correct. 

Faraday's general analysis of the latex of the Hevea is: 

Caoutchouc 30.70 

Albuminous extractive and saline matter 12.93 

Water 56.37 

The specific gravity of the latex quoted was 1.012. 
The crude rubber itself is made up of the following general 
composition : Carbon, 87.5 ; hydrogen, 12.5. 



CHAPTER XIV. 

PHYSICAL TESTS AND METHODS OF ANALYSIS OF VULCANIZED INDIA- 
RUBBER. 

It long has been the boast of expert rubber superintendents 
and manufacturers that they found Httle trouble in matching com- 
pounds. As a matter of fact, some of them are marvelously 
expert. Given a small sample of vulcanized rubber in a familiar 
line, with a knowledge of the price at which it must be produced, 
they are able in a majority of instances, by their knowledge of 
rubber and of compounding ingredients, to get a result that is 
apparently similar, and without much experimenting. 

In certain instances, however, they fail, principally where a 
new product is brought in for matching, to which is attached an 
extraordinarily low price. The usual refuge in such a case for- 
merly was the assertion that the manufacturer was losing money 
on that particular line of goods. But this has been so often dis- 
proved, and the sample found to be both an original and better 
compound, that this excuse is not often heard nowadays. 

The factory expert gaged his sample, no matter how expert 
he might be, by purely physical rules. The smell told him what 
kind of rubber was used, whether Para or African, and usually 
whether reclaimed rubber was present. The strength and the 
weight of the sample gave him an indication as to the amount 
of adulteration. The color also had its suggestions as to material 
contained in it, but the knowledge thus shown often was very far 
from being exact. 

Nor was the general result very much better when informa- 
tion was purchased from employes, or points secured through 
quizzing the supply men. The best course for the rubber super- 
intendent to pursue, therefore, is to put his knowledge up against 
that of the expert chemist, when the two, working together, can 
usually match better than the original. It is better if the chemist 
be familiar with the practical manipulation of rubber, for the un- 
familiar chemist has in many cases brought science into consider- 
able disrepute in the factory. 

Certain rubber compounds, in spite of the most careful analy- 

260 



TESTING MACHINES. 261 

sis by expert chemists, have remained, and probably will remain, 
profound secrets. For ordinary work, however, there ought to 
be no trouble in getting a fair analysis. The following descrip- 
tions of processes employed in the analysis of vulcanized rubbber 
are given chiefly that the rubber superintendent who views chem- 
istry as a dark and deep mystery may have some knowledge of 
what the chemist is about when he seeks his assistance. Before 
beginning on chemical analysis a few words more concerning 
physical tests may not be amiss. 

In the case of many kinds of goods there is a great variety 
of appliances that form really valuable tests as to their durability, 
tensile strength, wearing quality, and so on. As a rule, these aim 
to reproduce the work that the vulcanized article is obliged to 
endure in actual service. In rubber boots and shoes, for example, 
a machine is employed which bends the shoe exactly as it is bent 
when the wearer is walking, and at the same time gives a friction 
motion on the sole. This is run at a high rate of speed, so that a 
week's wear on a machine like this would correspond to a month 
of service in actual use. 

A machine is also used for testing air-brake hose which coun- 
terfeits the swing and kinking motion that the hose gets in actual 
service. This is run at a very high rate of speed, and the hose 
which stands this sort of usage longest is supposed to be adapted 
to endure the longest time in actual use. 

Tires, both pneumatic and solid, are tested by being put on a 
wheel rim and run what is equivalent to hundreds and thousands 
of miles over roughened surfaces upon which they are pressed by 
a lever carrying heavy weight. These mechanical contrivances 
are valuable in showing the severe usage that rubber will often 
stand, but none of them are exact parallels to absolute service, 
for as a rule they are more severe, particularly in the intense 
heating that may come to the rubber from high speeds and great 
friction. 

Manufacturers and purchasers of rubber goods have also 
many simple and excellent tests for approximating the value of 
the rubber. In belt and hose covers and tubes, a bit of the rubber 
is cut from the fabric and stretched to show its tensile strength. 
The fabric is also pulled apart, and the integrity of the friction 



262 



ANALYSES OF RUBBER. 



proved by the way it resists such separation. Rubber springs 
sometimes have been placed under a steam hammer which was 
allowed to drop upon them, the results being noted and that com- 
pound standing up longest being considered the best. 

An English manufacturer following out this test, got some 
interesting, if not valuable, results. He took a piece of vulcanized 
India-rubber i^ inches thick and with 2 inches area, and placed it 
under a steam hammer of five tons, which first rested upon the 
rubber without effect. The hammer was then raised two feet and 
dropped upon it without injury, then lifted four feet, when the 
cake was torn, but none of its elasticity was destroyed. More 
severe trials were then made. A block of vulcanized India-rubber 
was placed between two cannon balls, with the whole power of 
the heaviest steam hammer employed ; the iron spheres split the 
block, but the elasticity of the rubber still remained. 

The ordnance department of the United States government 
some years ago inaugurated some very interesting tests of vul- 
canized rubber at the arsenal at Watertown, Massachusetts, the 
results of which are appended : 



No. 1. 



Applied Loads. 


Mean Length. 


Compression. 


Compression 
Sets. 


Middle Diameter. 


Pounds. 


Inches. 


Inches. 


Inch. 


Inches. 





572 







6.10 


1,000 


S-32 


.40 


0." 


6.38 


2,000 


4.84 


.88 


.10 


6.72 


3,000 


4-47 


1-25 


.18 


7.06 


4,000 


403 


1.69 


.29 


7.48 


5,000 


370 


2.02 


•33 


7^79 


6,000 


3-40 


2.32 


•37 


8.12 


7,000 


3-M 


2.58 


.42 


8.44 


8,000 


2.96 


2.76 


•39* 


8.73 


9,000 


2.80 


2.92 


•51 


8.92 


10,000 


2.68 


3-04 


.58 


9.1 1 


11,000 


2.60 


3.12 


.52* 


9.24 


12,000 


2.50 


3.22 


.60 


9.42 


13,000 


2.45 


3.27 


.67 


9-5S 


14,000 


2.36 


3-36 


•73 


9.68 


15,000 


2.31 


3-41 


•74 


9-77 





5-15 






6.71 



* Before these sets were taken the load on the rubber was reduced to 500 pounds, then 
increased to 1,000 pounds, and the sets then measured. 



TESTS OF VULCANIZED RUBBER. 



263 



The second test was of new rubber gun-carriage springs, in 
which the compression sets were determined under the initial load, 
the end diameters approximate under load. The length of the 
rubber spring was 6.03 inches ; the diameter 6.03 inches ; the diam- 
eter of core 1.04 inches; the sectional area 27.71 square inches; 
and the weight 1 1 pounds : 



No. 2. 



Applied 


Length. 


Compres- Coi 
sion. son 


npres- 
Sets. 


Diameters. 


Middle 
Diam. Under 
Initial Load. 


Loads. 


End. 


Middle 


Pounds. 


Inches. 


Inches. It 


tch. 


Inches. 


Inches. 


Inches. 


500 


5-87 


0. 




6.03 


6.12 


6.12 


1,000 


5.70 


• 17 


02 


6.03 


6.24 


6.15 


1,500 


551 


•36 


03 


6.03 


6.35 


6.15 


2,000 


5-34 


•53 


06 


6.03 


6.48 


6.18 


2,500 


5-13 


•74 


07 


6.03 


6.64 


6.18 


3,000 


5.00 


.87 


07 


6.10 


6.76 


6.18 


3.500 


4.81 


1.06 


09 


6.15 


6.87 


6.18 


4,000 


4-65 


1.22 


08 


6.16 


7.00 


6.18 


4,500 


4.50 


1-37 


08 


6.18 


7-15 


6.19 


5,000 


4-35 


152 


02 


6.29 


7.26 


6.19 


5.500 


4.20 


1.67 


12 


6.38 


7.41 


6.19 


6,000 


4.06 


1.81 


19 


6.43 


^■§f 


6.19 


6,500 


3-95 


1.92 


03 


6.50 


7.66 


6.21 


7,000 


3-83 


2.04 


IS 


6.64 


7-77 


6.21 


7,500 


370 


2.17 


15 


6.70 


7.91 


6.22 


8,000 


3.62 


2.25 


15 


6.78 


8.02 


6.22 


8,500 


3-52 


2-35 


16 


6.89 


8.13 


6.22 


9,000 


3-43 


2.44 


16 


6.96 


8.24 


6.23 


9,500 


3-35 


2.52 


17 


7.06 


8.34 


6.24 


10,000 


3-25 


2.62 


17 


7.25 


8.46 


6.25 



The spring was then removed from the testing-machine, 
measured, and its length was 5.90 inches; middle diameter 6.08 
inches. After it had rested 20 minutes the length was 6 inches, 
and the middle diameter 6.06 inches. It was then placed again in 
the testing machine and the figures on the following page taken. 

When removed its measurements were: Length 5.86 inches; 
middle diameter 6.24 inches ; end diameter 5.90 inches ; the ends 
were concave, V. sine .o5 and .08 inches. After six hours' rest it 
recovered in length to 5.96 inches. 



264 



ANALYSES OF RUBBER. 



No. 3. 











Diameter. 


Middle 


Applied 
Loads. 


Length. 


Compres- 


Compres- 






Diam. Under 
Initial Load 


sion. 


sion Sets. 


Ends. 


Middle. 


Pounds. 


Inches. 


Inches. 


Inch. 


Inches. 


Inches. 


Inches. 


500 


5-84 


•03 


•03 


6.01 


6.15 


6.15 


6,000 


4.00 


1.87 




6-55 


7.63 




10,000 


3-29 


2.58 




7.25 


8.40 




10,500 


3.21 


2.66 




7-35 


8.48 




11,000 


3.16 


2.71 




7 39 


8.54 




11,500 


3" 


2.76 




7.46 


8.60 




1 2,000 


3.06 


2.81 


•17 


7-55 


8.67 


6.26 


1 3,000 


2.94 


2-93 




7-74 


8.86 




1 4,000 


2.86 


3.01 




7.86 


8.97 




1 5,000 


2.80 


3-07 


.22 


7-94 


9.04 


6.30 


1 6,000 


2.71 


3.16 




8.10 


9.20 




17,000 


2.65 


3.22 




8.20 


9.28 




18,000 


2.61 


3.26 




8.27 


9-35 




19,000 


2.56 


3-31 




8.36 


9.42 




20,000 


2-53 


3-34 


•30 


8.43 


9-47 


6.37 



In the next test the length of the spring was 6.06 inches ; 
diameter, 5.97 inches; diameter of core 1.06 inches; sectional area 
27.11 square inches; weight, 11 pounds. 



No. 4. 



Applied 


Length. 


Compres- 


Compres- 


Diameter. 


Middle 








Diam.Under 










End. 


Middle. 


Initial Load. 


Pounds. 


Inches. 


Inches. 


Inch. 


Inches. 


Inches. 


Inches. 


500 


.590 


0. 


0. 


5-97 


6.07 


6.07 


1,000 


5-75 


•15 


.02 


5-97 


6.16 


6.07 


1,500 


5-59 


•31 


.02 


5-97 


6.27 


6.08 


2,000 


5-41 


•49 


.06 


5.98 


6.38 


6.10 


2,500 


5.25 


.65 


.05 


6.02 


6.48 


6.10 


3,000 


5.05 


.85 


.09 


6.05 


6.62 


6.12 


3,500 


4.90 


1. 00 


.08 


6.08 


6.73 


6.1 1 


4,000 


4.76 


1. 14 


.10 


6.14 


6.88 


6.12 


4,500 


4.61 


1.29 


.10 


6.20 


7.00 


6.12 ■ 


5,000 


4-47 


1-43 


.11 


6.25 


7.1 1 


6.12 


5,500 


4-33 


1-57 


.11 


6.31 


7.24 


6 14 


6,000 


421 


1.69 


.12 


6.37 


7-32 


6.15 



The measurements when removed from the machine were: 
Length, 5,98 inches; middle diameter 6 inches; end diameter 5.97 
inches. After it had rested 15 hours, it measured: Length 6.02 



TESTS OF VULCANIZED RUBBER. 



265 



inches; middle diameter 6 inches; end diameter 5.96 inches. It 
was then placed again in the machine and tests were resumed. 

No. 5. 





Length. 


Compres- 
sion. 


Compres- 
sion Sets. 


Diameter. 


Middle 
Diam.Under 
Initial Load. 


Loads. 


End. 


Middle. 


Pounds. 


Inches. 


Inches. 


Inch. 


Inches. 


Inches. 


Inches. 


500 


5.90 


0, 




5-97 


6.08 


6.08 


6,000 


4.27 


1.63 




6.3s 


7.30 




6,500 


4.12 


1.78 


.08 


6.38 


7.41 


6.1 1 


7,000 


4.00 


1.90 


.09 


6.60 


7-55 


6.12 


7,500 


3-90 


2.00 


.10 


6.57 


7.62 


6.14 


8,000 


3-82 


2.08 


.10 


6.65 


7-73 


6.12 


8,500 


3-72 


2.18 


.11 


6.75 


7.82 


6.14 


9,000 


3.62 


2.28 


• 14 


6.84 


7-93 


6.16 


9,500 


3-52 


2.38 


.14 


6-93 


8.03 


6.17 


10,000 


345 


2.45 


.16 


7.00 


8.1 1 


6.17 



The spring was then removed from the testing machine and 
its measurements were: Length 5.92 inches; middle diameter, 
6.09 inches. Measurements after the spring had rested one hour 
showed: Length, 5.98 inches; middle diameter, 6.06 inches; end 
diameter, 5.95 inches. The spring was again placed in the 
machine and tests resumed. 

No. 6. 



Applied 


Length. 


Compres- 
sion. 


Compres- 
sion Sets. 


Diameter. 


Middle 
Diam.Under 
Initial Load 


Loads. 


End. 


Middle. 


Pounds. 


Inches. 


Inches. 


Inch. 


Inches. 


Inches. 


Inches. 


500 


5.88 


0.7 


.07 


597 


6.13 


6.13 


6,000 


4.09 


1.81 




6.41 


7-47 




10,000 


3-46 


2.44 




7.00 


8.12 




10,500 


338 


2.52 




7.09 


8.22 




11,000 


3-34 


2.56 




7-15 


8.27 




11,500 


3-27 


2.63 




7.21 


8.36 




12,000 


3-17 


2.73 


.22 


7.26 


8.40 


6.22 


13,000 


3.10 


2.80 




7.46 


8.57 




14,000 


3.02 


2.88 




7.51 


8.67 




15,000 


2.90 


3.00 


.26 


7.66 


8.70 


6.27 


16,000 


2.84 


3.06 




7.84 


8.95 




17,000 


2.79 


3-" 




7.90 


9.02 




18,000 


275 


3.16 




7.97 


9.06 




19,000 


2.70 


3.20 




8.05 


9-13 




20,000 


2.68 


3.22 


■1>1 


8.11 


9.19 


6.36 



266 



ANALYSES OF RUBBER. 



(the preceding table continued.) 



Applied Loads. 


Length. 


Compres- 
sion. 


Applied Loads. 


Length. 


Compres- 
sion. 


Pounds. 


Inches. 


Inches. 


Pounds. 


Inches. 


Inches. 


1,000 


5-43 


•47 


11,000 


3-05 


2.85 


2,000 


5.10 


.80 


12,000 


2.98 


2.82 


3,000 


4.75 


115 


13,000 


2.91 


2.99 


4,000 


4-43 


1.47 


14,000 


2.85 


3-05 


5,000 


4.10 


1.80 


15,000 


2.81 


309 


6,000 


3.80 


2.10 


16,000 


2.78 


312 


7,000 


3-58 


232 


17,000 


2.74 


3-16 


8,000 


3-38 


2.52 


18,000 


2.70 


3.20 


9^000 


325 


2.65 


19,000 


2.67 


323 


10,000 


3-15 


2.75 


20,000 


2.63 


3-27 



Time for loading, three minutes. The spring was then 
removed from the testing machine and its measurements showed : 
Length, 5.81 inches; middle diameter, 6.25 inches; end diameter, 
5.87 inches; ends concave, V. sine, .08 and .10 inch. It recovered 
in length to 5.93 inches after four hours' rest. 

The French navy also inaugurated a series of tests for rub- 
ber belting which are of interest. The first test related to elas- 
ticity. Samples from the cover were first put into a steam vul- 
canizer for 48 hours, under a pressure of 5 atmospheres, which 
they should stand without losing their elasticity. The samples 
are then placed under a pressure of 85.5 pounds per square inch 
on the grating of a valve box, and given strokes at the rate of 100 
per minute. They were expected to stand 9,100 strokes, while 
samples not tested by the steam should stand 17,100 strokes. 
Strips from the cover that had received the steam treatment, 6-I0 
of an inch square on cross section, and 8 inches long, fastened 
at each end and elongated 3.9 inches, were not expected to break 
when stretched 8 inches more, this being repeated 22 times a 
minute for 24 hours. Strips that had not been treated to the 
steam bath should resist the same treatment for 100 hours. 
These tests of course applied to high grade compounds only. 

The analysis of vulcanized India-rubber should give the fol- 
lowing information : 

Amount of India-rubber, 
Amount of India-rubber resins, 
Amount of substitutes, 



HENRIQ UES'S METHODS. 267 

Amount of free, fatty resin, and mineral oils, resin, paraffine, and 
bituminous bodies. 

Amount of sulphur of vulcanization. 
Amount of sulphur and chlorine in substitute, 
Amount of free sulphur. 
Amount of mineral matters. 

The mineral matters embrace metallic sulphides and oxides, 
inert mineral substances such as whiting and barytes, and sub- 
stances imparting special properties such as asbestos, graphite, 
pumice, etc. 

According to Carl Otto Weber, Ph.D., F.C.S., and to Percy 
Carter Bell, F.I.C., F.C.S., Dr. Robert Henriques has by his 
methods of analysis solved the problem that troubled the analysts 
more than any other, which was that of determining the amount 
of oil substitutes found in India-rubber compounds. 

Dr. Henriques's methods are as follows: Fuming nitric acid 
to the amount of 20 c.c. is placed in a small dish covered with 
a funnel, through the stem of which 3 to 4 grams of rubber are 
slowly added. When the action has ceased, the dish is warmed 
gently on a water bath until the contents are of the consistency 
of a thin syrup. There are then added 4 grams of a mixture of 4 
parts sodium carbonate and 3 parts of potassium nitrate, after 
which it is carefully fused, and treated with dilute muriatic acid, 
then evaporated to dryness to render silica, if present, insoluble, 
redissolved by adding a little nitric acid, and, last, the sulphuric 
acid is precipitated with barium chloride. The residue of silica 
may contain sulphates of lead or of barium. Ammonium acetate 
dissolves the former. 

In estimating the sulphur of vulcanization, and also the 
excess of sulphur, they must be separated from that present in the 
form of sulphates and sulphides. This is done in the following 
manner: The sample of rubber is dissolved in that fraction of 
ordinary petroleum which distills over at from 140° to 250° C, 
being kept in the solvent at a boiling temperature for two days. 
From 5 to 15 grams of the sample are placed in a weighed flask, 
and, after adding about 150 c.c. petroleum free from sulphur, all 
the inorganic matter is dissolved by heating the flask with reflux 
condenser at about 150° C. The subsequent processes are the 
filtering of the solution, the careful washing of the flask with hot 



268 ANALYSES OF RUBBER. 

petroleum, and the rinsing of both flask and filter with petroleum 
ether. Those substances insoluble in petroleum are determined by 
weighing on the tared filter at iio° C. 

The sulphur in this residue, which is easily determined, when 
deducted from the total sulphur of the sample, gives the amount 
of the free sulphur, and sulphur of vulcanization. If the rubber 
contains metallic oxides or carbonates, some of the sulphur may 
have been oxidized to sulphuric acid, and the results noted above 
may be too low. 

The rubber substitutes in the compound are completely and 
easily soluble in alcoholic potash. The following is the manner 
of this analysis: From 3 to 5 grams of the rubber compound, 
finely divided, is boiled for about 8 hours in ten times its weight 
of alcoholic soda, 8 per cent, strong. The solution, diluted with 
water, is freed from the alcohol by means of a water bath, after 
which the residue on a weighed filter is washed, dried, and 
weighed. To determine the residue on ignition of the extracted 
residue, one gram is taken and the ignition performed in the 
presence of ammonium nitrate. If now the substance extracted 
from the rubber be free from chlorine, it may either consist of" 
free oil, or be derived from black rubber substitute. In the latter 
case, it must contain at least 10 per cent, of sulphur, but in the 
former, only traces of sulphur will be present. An estimation 
therefore of the chlorine and of the sulphur in the alcoholic ex- 
tract determines the presence of white substitute, black substitute, 
or sulphur. 

In using caustic alkali a certain amount of the alkali will be 
retained, the amount of which must be determined, if correct 
figures are to be secured. Repeated washings in dilute muriatic 
acid remove this, and allow of its determination. 

The following data are necessary in the analysis of vulcan- 
ized rubber containing substitute or oil: (i) The total sulphur; 
(2) the total ash; (3) the weight of the substance after extrac- 
tion with alcoholic soda; (4) the sulphur, the ash, and the sul- 
phur in the extracted fatty acids all to be found in the third sub- 
stance. Also, the weight of the substance after extraction with 
alcoholic soda. From 1.5 to 2 grams of substance are used, the 
extraction being twice repeated, each boiling being from two to 



VARIOUS TESTS. 269 

three hours. The quantity of rubber dissolved by the alcoholic 
soda is deducted from the weight of the total extract. This cor- 
rection averages 2.5 per cent. 

From the above figures, the percentage of rubber and fatty 
acids may be calculated by equations, which read : 

ICX) 

Rubber = (Weight of substance after extraction of alcoholic 

97.5 soda — its sulphur — its ash). 

The fatty acids from this equation : 

Fatty acids ^ 100 — (total sulphur -j- total ash 4- percentage of 

rubber found from the foregoing equation). 

The sulphur contained in the rubber substitute is represented 
by assuming that quantity to be about equal to that of the fatty 
acids in white substitute and about 1.5 per cent, larger than the 
quantity of fatty acids in brown substitute. The difference be- 
tween the total sulphur and the sulphur in the substitute is the 
sulphur of vulcanization. Asphalt being often present in rubber 
compounds, by first dissolving the free sulphur by treatment with 
alcoholic soda, and then dissolving the asphalt out by means of 
nitrobenzene, it is easily determined. The presence of mineral 
oils, parafiine, and resins are the only things that interefere with 
this means of extraction. 

The following tests are credited to C. A. Lobuy de Bruyn : 

1. Extract Test (Henriques's method). — Three grams of 
the finely divided sample when boiled for six hours with 50 c.c. 
of a 6 per cent, alcoholic solution of caustic soda should not lose 
more than 8 per cent., the loss to be calculated upon the organic 
substance of the sample. The extract should contain sulphur and 
rubber resins. 

2. Dry Heat Test. — Two grams of the finely divided sample 
are heated to 135° C. for two hours. When cold the sample 
should not have suffered any alteration and should show a loss of 
weight not exceeding 1.5 per cent. 

3. Moist Heat Test. — A small piece of the sample is sealed 
in a glass tube half filled with water. The tube is then heated to 
170° C. for four hours. The sample should not be affected by 
this treatment. 



270 ANALYSES OF RUBBER. 

4. Ash. — About I gram of the sample is fused, decomposed, 
and partly ignited over a small flame in a porcelain crucible. The 
heat is then increased and ignition completed. 

Dr. C. Reinhardt, in Dingler's Polytechnisches Journal, 
writes as follows on the analysis of vulcanized India-rubber: 
^'The determination of the ashes is effected by gradually heating 
in a covered crucible .0182 ounce of the product until the cessa- 
tion of gaseous liberation. The calcination is finished in an open 
crucible, care being taken not to heat too much, so as to avoid the 
losses due to the volatilization of the substances composing the 
ashes. To determine the proportion of mineral substances (with 
the exception of sulphur) .0182 ounce of India-rubber fragments is 
moistened with 1.2 cubic inch of D nitric acid (= 14.), and heat- 
ing takes place in a water bath for five to seven minutes, until 
complete dissolution ensues. Dry evaporation takes place in the 
water bath, followed by moistening with hydrochloric acid and 
dissolution in water. The residue is formed of sulphate of 
barium and silica acid ; the quantitative analysis of the substances 
contained in the liquid (oxide of zinc, lime, magnesia, oxide 
of iron, and alumina) being made according to the usual methods. 
To determine the total of sulphur there is treated .0357 ounce of 
the product (while heated) with 1.2 cubic inches of nitric acid; 
chlorate of potash being gradually added until oxidation is 
complete. After evaporation and dissolution in water, with the 
addition of hydrochloric acid, follows precipitation. Then takes 
place the quantitative analysis of the sulphuric acid by the 
chloruret of barium and of the remainder of the sulphuric acid in 
the insoluble residue of sulphate of baryta. It is possible to deter- 
mine the quantity of sulphur added for the vulcanization by burn- 
ing the product in a current of oxygen at a low temperature by 
passing the vapors across hydrochloric acid containing bromine, 
and by analyzing quantitatively the sulphuric acid formed in the 
condition of sulphate of baryta. The India-rubber can likewise 
be distilled in glass tubes and the quantity of sulphur in the dis- 
tilled liquor can be ascertained." 

In Dr. Weber's exceedingly valuable article printed in the 
Journal of the Society of Chemical Industry, the steps in analysis 
are thus shewn: 



DETERMINING RUBBER SUBSTITUTES. 271 

SUMMARY OF WEBER's METHODS OF ANALYSIS. 



I. Acetone (10 runs in Soxhlet tube). 



Fatty and 

Mineral 

Oils, 

Resins and 

Free 

Sulphur. 



II. Boiling Alcoholic Soda (8 per cent). 



Rubber 
Substitutes. 



III. Cold Nitrobenzole. 



Asphaltum. 



IV. Boiling Nitrobenzole (Soxhlet 
tube). 



Rubber and 
Sulphur 
of Vul- 
canization. 



V. Residue. 



Mineral matters and 
free carbon. 



The rubber substitutes are determined by extracting in 
alcoholic soda solution and asphaltum by cold nitrobenzene, both of 
these methods being Henriques's. The rubber is separated by 
extraction with boiling nitrobenzene in the Soxhlet tube. Starch 
is dissolved out by boiling water. The mineral and carbonaceous 
matters are determined in the final residue. The matters in the 
acetone extract, the rubber and mineral matters are determined by 
weighing after evaporation. Substitutes and asphaltum are best 
determined in the loss of weight operated upon. 

Of the various forms of sulphur occurring in rubber, the 
determination of free sulphur and sulphur of vulcanization is of 
great importance. The estimation of the free sulphur is made in 
t^e acetone extract. Not all the sulphur in this extract is free, as 
the presence of rubber substitutes in the sample means that the 
extracts will contain sulphides of the fatty acids, also the sul- 
phides produced by the action of free sulphur on the resins always 
found in rubber. To estimate the sulphur in the acetone extract, 
add 20 c.c. of a solution of pure sodium sulphide and caustic 
soda and heat the mixture on a water bath for an hour. Dilute 
the solution with warm water, and precipitate the fatty acids by 
adding a slight excess of barium hydrate. Filter, wash, and make 
up the filtrate to 300 c.c. and estimate the sulphur in an aliquot 
part. 



272 ANALYSES OF RUBBER. 

In determining the sulphur of vulcanization, the free sulphur 
must first be removed, and for this purpose, the acetone extract 
answers very well. In every case the sulphur of vulcanization 
should be estimated direct. The solution of rubber in nitroben- 
zene is therefore distilled under reduced pressure. The flask con- 
taining the non-volatile residue is then dried at 140° C, and then 
oxidized with fuming nitric acid. When the residue has finally 
dissolved, the solution is poured into a platinum dish, the flask 
being rinsed with warm nitric acid. The residue is then evapo- 
rated on the water bath, fused with carbonate of soda, dissolved 
in water, oxidized with bromine, acidulated with muriatic acid, 
and the sulphur precipitated with barium chloride. The sulphur 
in the asphaltum which is in the cold nitrobenzole solution is 
determined in a similar manner. 

TORREY'S METHOD OF DETERMINING RUBBER. 

Joseph Torrey, Ph.D., who has added much to rubber re- 
search, uses the following method for examining both vulcanized 
and unvulcanized rubbers : 

"i. Oils, resins and free sulphur — Acetone extract. 

"2. Pitch, tar, asphalt, etc. — Pyridine extract on residue 
from I, 

"3. Oily substitutes — Alcoholic soda extract on residue 
from 2. 

"4. Mineral matter — Residue from and nitro naphthaline 
extraction of residue from 3, or by incineration. 

"I have not included the 'sulphur of vulcanization' determina- 
tion because in very many cases it is not important, or can be 
judged closely enough. It would however, be convenient to have 
a short method of determining in the residue from 3 — or a por- 
tion of it — the amount of pure rubber present. 

"The methods described by Weber and Harries, apart from 
the recent criticisms by Alexander and Harries, are long and 
expensive. They require, moreover, no small amount of manipu- 
lative skill. I venture, therefore, to submit the following as a 
simple and inexpensive method requiring little apparatus and 
capable of yielding good results in comparatively untrained hands. 

"Let it be distinctly understood, however, that I do not offer 



TORREY'S METHOD. 273 

this as a suitable method for valuing crude rubber, though I have 
in many cases obtained good results by its use. If such a method 
is desired the precipitation method recently described by Fendler 
gives quick and satisfactory results, as I have found in several 
years' experience with it. 

"The new method is founded on the fact that when rubber is 
heated with pure nitric acid of specific gravity 1.42 under fairly 
constant conditions it is converted into a body which dissolves 
completely in caustic alkaline solutions with production of a deep 
red color. I have not studied this body in detail, except to satisfy 
myself that the same weight of pure rubber, when treated as 
described and diluted with water to a definite volume, always 
gives the same tint. It makes no difference whether the rubber 
be vulcanized or not, in the ordinary filling and weighing mineral 
bodies used in vulcanized rubber goods have no effect on the final 
tint. 

"Resins sometimes interfere, sometimes not. Dark substi- 
tutes interfere, and must be removed. Pitch, tar, asphalt, etc., 
also interfere. The proper place for the determination is after 
No. 3 in the scheme given above. I will now describe the prepa- 
ration of a rubber solution of known strength, and having a con- 
venient standard tint; and then show how the solution thus pre- 
pared is used as a standard of comparison with other solutions 
similarly prepared, but containing unknown amounts of rubber. 

"o.i gram of pure, precipitated rubber is placed in a test 
tube and treated with 2 c.c. of pure nitric acid, specific gravity 
1.42. The tube is placed in a beaker of water heated to 50-60° C. 
till the action is entirely over; then to 90-100° for 20 minutes. 

"Add first ID c.c. distilled water, then 20 c.c. of caustic soda 
solution (i part stick caustic soda in 4 parts water). Stir or 
shake gently; dilute with 10 c.c. more water, filter, and wash the 
filter paper with water till the washings are colorless. Finally 
dilute the whole to 250 c.c. ; mix thoroughly, and transfer about 
100 c.c. to a test tube of, say, 120 c.c. capacity. This solution 
represents a concentration of o.i gram rubber in 250 c.c. and 
has a straw tint which experience shows to be a convenient one. 

"Suppose now that we have in hand the residue from opera- 
tions I, 2, and 3, we proceed with it as follows: 



274 ANALYSES OF RUBBER. 

"Weigh carefully o.i gram and treat with 2 c.c. of nitric 
acid, specific gravity 1.42, in exactly the same way as just de- 
scribed. Add the same quantities of water and caustic soda 
solution as before, filter, and wash till the washings are colorless. 
Finally transfer the solution (or half of it if the tint is very deep) 
to a test tube having the same internal diameter as that contained 
in the standard; and dilute, with constant stirring, till the 
standard tint is exactly matched. Measure carefully the volume 
of the solution under test. Call it V. Then the calculation of 
the percentage of rubber in the original mixing is accomplished 
by the equation — 

a V 

250 
Where /'=The percentage required. 

F=The volume of the solution under test when at standard 

tint. 
a=ioo per cent, minus the total percentage lost in operations 
I, 2 and 3. 

"If only half the test solution has been diluted this result 
must, of course, be doubled. The results are good. Duplicates 
usually agree with 0.5 per cent. A table is appended showing a 
few results. 

"As to the composition of these samples, I will merely say 
that they contain no substitutes and no tarry substances. The 
rubber used was a good Borneo, containing 1.5 per cent, resin. 
The content of rubber according to the proportion in which the 
materials were weighed out would be from 40 to 50 per cent., but 
I do not feel at all sure that one can assume that a mixing, 
especially when vulcanized, contains the calculative proportion of 
unaltered rubber. 

"I have had about four months' experience with the method, 
and the best evidence of its trustworthiness is that in every case 
where I have been lead to results which I at first distrusted, the 
final outcome has been the discovery of unsuspected circumstances 
which vindicated the accuracy of the suspected results. 

"Finally, it may be pointed out that the determination of 
mineral matter not easy at all by any of the present methods can, 
by making use of the direct determinations indicated in the above 



TEST FOR FARINA. 275 

plan of analysis, be made the only factor determined by difference. 
I am of the opinion that results obtained by this method will be 
found fully as trustworthy as those by any method at present 
known." 

Sample Number. Unvulcanized. Vulcanized. 

No. I 4726 4700 

47.43 47.19 

No. 2 41.92 4118 

41.36 41.74 

No. 3 4589 46.19 

44.93 45-12 

No. 4 47-75 47-00 

47-39 4756 

No. 5 47-19 47-39 

46.62 46.43 

No. 6 49.26 49.44 

48.52 49.82 

Test for Farina in Rubber. — Those manufacturers who now 
and then receive lots of Para rubber adulterated with the starch like 
meal of the mandioc or cassava plant — also called farinha flour — 
may be interested to know of the method of detecting such adul- 
teration employed by Mr. Walter E. Piper. Starch is a charac- 
teristic test of iodine, forming with it a deep blue compound. Mr. 
Piper uses a solution in water of iodine and potassium iodide, 
which is applied with a brush to the interior of a "ham" of fine 
Para. If there is farinaceous matter present it will speedily take 
on a bluish appearance. Ordinarily the adulterant is not visible, 
and the manufacturer becomes aware of it only from the extra 
loss in washing- rubber. 

Analyses of Caoutchouc molecules. — Professor Dr. C. 
Harries's experiments show that ozone may be readily added to 
the Caoutchouc molecule, and he proved that there are two double 
sets of bonds for C^,, Hjg. The "Ozonite" obtained is an explosive 
body and it has a chemical formula of (CioHi6 06)2. Professor 
Harries analyzed this "ozonite" into levulinic acid, which is an 
acetone, and which is a derivative from succinic acid. The 
mystery which has surrounded the Caoutchouc molecule has by 
this work been unveiled. 



CHAPTER XV. 

GUTTA-PERCHA-ITS SOURCES, PROPERTIES, MANIPULATION, AND 
PRINCIPAL USES. 

Gutta-percha^ which was introduced into Europe from 
Singapore in 1843, was for a while confounded with India- 
rubber, from which it differs in some very important particu- 
lars. It becomes soft and plastic on immersion in hot water, 
retaining the shape then given it on cooling, whereupon it 
becomes hard, but not brittle like other gums. India-rubber, 
on the other hand, does not soften in hot water, and retains its 
original elasticity and strength unimpaired. The water, as 
such, exercises no softening action on Gutta-percha, the effect 
being purely one of temperature, which may equally well be 
produced by hot air, only somewhat more slowly. The degree 
of heat required depends upon the quality of the material, but 
even the hardest kinds become plastic above 150° F. Heated 
in air considerably above the boiling point of water, Gutta- 
percha decomposes and finally ignites, burning with a lumi- 
nous smoky flame and emitting a pungent odor resembling that 
from burning rubber. If heated in a vacuum, gaseous and 
liquid products are obtained similar to those resulting from 
the distillation of rubber. The liquid which distills over con- 
sists chiefly of hydrocarbons of the terpene series, which form 
an excellent solvent for Caoutchouc. The two most important 
are isoprene and caoutchine, which are identical with the liquids 
by the same names obtained from India-rubber. Since 
these products can also be obtained from other sources, Dr. 
Eugene Obach and others have observed that they may yet 
form a stepping-stone in the synthetical production of India- 
rubber and Gutta-percha from the lower terpenes. 

A curious physical characteristic of Gutta-percha is that 
when it has been softened in water, although it is so plastic 
that it will reproduce the most delicate impressions, it will 
bear blows from hammers or allow itself to be thrown against 
a stone wall without being at all marred. The reason for this 
is that it contains a large amount of air. By placing the 

276 



COMPONENTS OF GUTTA-PERCHA. 277 

Gutta-percha under a bell jar immersed in mineral oil, when 
a vacuum is produced, a large amount of air is evolved from 
the g"um, and it will be found to have lost the property of 
hardening on cooling, its substance being like a tough greasy 
leather. 

Nowhere on the globe have genuine Gutta-percha trees 
been found outside of a rectangular area embracing portions 
of the Malay peninsula, Borneo, Sumatra, and some adjacent 
smaller islands. Strange to say, the occurrence of these trees 
has not been established in Java, or the Celebes, though trees 
producing inferior qualities are found in the Philippines. 
These trees belong to the natural order Sapotacece; the principal 
genera and species will be noted further on. 

According to Payen's analysis, verified by later chemists, 
Gutta-percha contains three components: (i) a substance in- 
soluble in cold and in boiling alcohol, which he termed pure 
gutta; (2) a crystalline white resin, soluble in hot, but not in cold 
alcohol, which he called alhane; (3) an amorphous yellow resin, 
which he named fluavile. Pure gutta is insoluble in ether and 
light petroleum spirit at ordinary temperatures, whereas both 
albane and fluavile dissolve readily in them. Gutta possesses 
all the valuable qualities of Gutta-percha, but in a much en- 
hanced degree; it becomes soft and plastic on heating, and 
hard and tenacious on cooling without being in the least 
brittle. But the resins themselves are either soft at ordinary 
temperatures, or, when hard, quite friable. It is, therefore, 
gutta which forms the useful constituent of Gutta-percha, 
and the resins are only accessory components, which, although 
admissible, and perhaps even desirable in a comparatively small 
amount, yet have a decidedly detrimental effect when they 
preponderate. Hence, in order to determine the technical 
value of a sample of Gutta-percha, it is necessary first to learn 
the relative proportion or ratio between gutta and resins. 
There must also be taken into account the water enclosed in 
the mass, and the coarse impurities — wood fibers, bark, sand, 
etc. — which are described as dirt. These components repre- 
sent the loss or waste to the manufacturer. 

While the relative proportion of gutta and resins forms an 



278 GUTTA-PERCHA. 

important criterion for estimating the commercial value of a 
sample, it is not in itself sufficient. Although the analysis of 
two different specimens may give the same result, the physical 
and mechanical properties, and, most important of all, the 
durability, may differ widely, owing to a difference in their 
molecular constitution. It will thus be seen that there are 
guttas and guttas. In addition to the qualitative analysis, it 
is necessary to scrutinize the gutta itself, which requires much 
judgment and experience. Analyses have been made of speci- 
mens which contained eight times as much gutta as resin ; 
others contained about an equal amount of both, and in others 
still the amount of resin was three times that of gutta. Sam- 
ples in which the percentage of resin reaches that of gutta, or 
surpasses it, are of a decidedly inferior description. These 
differences are due doubtless to the fact that the Gutta-percha 
of commerce is derived from trees of various species, and also 
in part to the treatment which the gum receives at the hands 
of the gatherers, who are suspected of mixing the product of 
different trees, to say nothing of adulterations of a more 
debasing character. 

The commercial classification of Gutta-percha is less satis- 
factory than that of India-rubber, since no standards have 
become fixed in the markets. While Para rubber, for instance, 
may be bought and sold by means of established designations, 
"Islands fine," "Upriver fine," and the like, no such practice 
exists with regard to Gutta-percha, Since all transactions in 
the latter are based upon samples, trade names and brands are 
little considered. However, "Macassar," and "Banjermassin," 
which are the names of districts producing Gutta-percha, were 
used formerly to indicate the highest quality, while "Sumatra" 
sorts were supposed to be less valuable, and "Borneo" the lowest 
of all. In a sense these designations have become merely com- 
mercial, no longer affording any indication of the origin of the 
Gutta-percha. At the same time, "Macassars" and "Banjer- 
massins" might vary with every new arrival, so that one was 
not certain, in buying one of the sorts named, to obtain particu- 
larly good Gutta-percha ; it might have been the very opposite. 

Innumerable sorts appear in the Singapore market — which 



PRINCIPAL GRADES. 279 

is the center of the Gutta-percha trade — but Df. Obach 
selected twelve of the principal brands as typical of all the 
rest, and divided them into four groups, for convenience in 
comparison, the best being named first. They are as follows, 
the designations being derived either from the countries of 
their origin or from the places of export : 

( I. Pahang — from the Malay peninsula. 

I. \ 2. Bulongan red — from Macassar, Borneo. 

' 3. Banjer red — from Banjermassin, South Borneo. 

( 4. Bagan goolie soondie — from Borneo. 

II- ] 5. Goolie red soondie — from Serapong, Borneo. 

' 6. Serapong goolie soondie — from Serapong, Borneo. 

i 7. Bulongan white — from Macassar, Borneo, 

in. J 8. Mixed white — from Borneo. 

( 9. Banjer white — from Banjermassin, South Borneo. 

i 10. Sarawak mixed — from Borneo. 

IV. < II. Padang reboiled — from Sumatra. 

( 12. Banca reboiled — from Banca. 

Group I comprises the three best kinds, derived from trees 
of the genus Dichopsis (known in continental Europe as Pala- 
quium). Group II comprises three kinds of the second order, 
derived probably from the genus Payena. Group III embraces 
the so-called "white gutta," of second and third grade, mostly of 
uncertain origin, but probably from Dichopsis polyantha. Group 
IV is made up of mixed materials, two of them being what is 
termed "reboiled" (an operation performed by the Chinese 
traders, who buy up odd lots, soften the materials in hot water, 
and make them into a more or less homogeneous average mix- 
ture). The "Sarawak mixed" lots mostly represent a very useful 
second-class material; the "reboiled" is decidedly inferior. This 
classification is based upon the results of 751 analyses of mixed 
lots, representing over 5,000,000 pounds of raw Gutta-percha, 
made by Dr. Obach, with a view to arriving at the relative pro- 
portions of gutta, resin, dirt, and water contained. The cleanest 
kind is the "Sarapong soondie," which contains only 3^ per cent, 
of dirt, but it is rather wet, having more than 25 per cent, of water. 
One of the least favorable materials is "Banjer white," which 
contains 33 1-3 per cent, of water and 15 per cent, of dirt, making 
in all nearly 50 per cent, of waste. When a raw material is very 
dirty and wet, it is noticeable on cutting the blocks open, and this 
is now the rule in the Singapore market. The blocks are then 



28o GUTTA-PERCHA. 

sorted out into several grades (two or three, sometimes more) 
according to their appearance, and valued accordingly, 

A grade of Gutta-percha which is nearly white in color and 
very brittle is apt to contain a large percentage of resin, which, 
as already explained, renders it of little value. In explanation of 
some of the terms in the preceeding classification, it may be said 
that Gutta-percha is obtained principally by cutting down the 
trees and ringing the bark at intervals of 12 to 18 inches along 
the trunk. The milky sap soon fills the grooves cut into the bark, 
and, in the better varieties, soon coagulates, when it is scraped oflF 
with a knife. In the case of inferior sorts, the milk requires more 
time to curdle, and has to be caught in receptacles placed under 
the tree. The collected milk is then gently boiled, either by itself 
or with the addition of water. The material obtained without the 
use of water is called a goolie, the other a gutta; but the two 
kinds are often mixed together. The goolie is more compact than 
the gutta, and has a dough-like smell. The word soondie is 
derived from the Malay term "Gutta-sundek," which is applied 
to the product of trees of the Payena species already referred to. 

The processes employed by manufacturers for cleaning raw 
Gutta-percha are either mechanical, or chemical Those of the 
first class will first be considered. Generally speaking, the raw 
Gutta-percha is either first cut up in a slicing machine and then 
softened in hot water, or the lumps are placed directly in hot 
water and the soft material transferred to the washing machine. 
There it is washed with hot water for a longer or shorter time, 
and then passed through a strainer. Next, as a rule, it is washed 
once more, then put into a kneading or masticating machine, to 
consolidate it and remove the mechanically enclosed water, and 
finally it goes to the rolling mill, to be made into sheets. 

The slicing machine or chopper now used is pretty much the 
same as that proposed by Charles Hancock, of England, in his 
patent (No. 11, 575, O.L.) of 1847, except that it is provided 
■with a greater number of fluted and serrated knives, instead of 
only three plain ones, fixed in the slots of a heavy iron disc. The 
blocks of Gutta-percha are packed into a trough and then forced 
against the rotating disc, the knives in which cut the material into 
thin slices. 



MECHANICAL TREATMENT. 281 

The washing machine consists of an iron roller of star-shaped 
section, enclosed in a cylindrical shell provided with one or two 
projections, or ribs, against which the Gutta-percha is forced in 
going round. The cylindrical shell is enclosed in a large iron 
case, filled with water, which is heated by means of direct steam. 
The dirt, as it is washed off, falls through the lower part of the 
cylindrical shell into the outer case, whence it is drawn off once 
in a while. This machine is developed from that described in the 
English patent of R. A. Brooman. (No. 10,550, O.L.) 

The Gutta-percha leaves the washing machine in a plastic 
state and passes to the straining machine — a strong iron cylinder 
with a perforated bottom, on which a number of discs of fine wire 
gauze have been placed. It has a piston which is driven home by 
hydraulic power, at a pressure of 1,500 to 2,000 pounds per 
square inch, squeezing the soft Gutta through the meshes of 
the gauze. 

The kneading machine or masticator resembles the washer, 
except that the roller is smaller in diameter, and the flutings are 
more numerous and not so deep. The Gutta-percha is kept hot 
during mastication and the water escapes in the form of steam 
through openings at the top. 

The mixing machine, introduced by Paul Pfeiderer, is similar 
to that used in the India-rubber, linoleum, and other similar 
industries. It is provided with peculiarly-shaped blades, working 
against one another. The machine is used for mixing the various 
sorts of Gutta-percha, in order to obtain a material of any requi- 
site properties, and also for blending Gutta-percha with pigments 
or other ingredients. The rolls can be heated by steam, but heat 
is developed by the kneading process itself, and care must be taken 
not to overheat the material. 

The Gutta-percha is next rolled into sheets, usually between 
I and ^ inch, and cut into lengths of 5 or 6 feet, and stacked away 
for use. The rolling machine takes the material from the mixer 
and squeezes it between parallel rollers, running it back and forth 
until it is cool and hard enough for cutting up. 

The average percentages of waste, shown by numerous 
analyses of the twelve brands of Gutta-percha catalogued on a 
preceding page, are about as follows : 



282 GUTTA-PERCHA. 

Pahang 34 Bulongan white 43 

Bulongan red 35 White mixed 35 

Banjer red 44 Banjer white 47 

Bagan goolie soondie 32 Sarawak mixed 44 

Goolie red soondie 27 Padang reboiled 44 

Serapong soondie 36 Banca reboiled 29 

The difference in the quality of various brands of Gutta- 
percha, measured by the relative proportions of gutta and resin, 
has already been mentioned. Of the sorts mentioned above, 
"Banca reboiled" shows a comparatively small loss in cleaning, 
but it is the least valuable on the list, being low in gutta, whereas 
"Pahang," though losing more in the cleaning process, is by far 
the most valuable sort in the market, because so rich in gutta. 
Gutta-percha imported in recent years loses more in cleaning than 
formerly; Dr. Obach, in 1898, estimated the loss as almost twice 
as great as formerly. 

The chemical washing process was suggested by Charles 
Hancock, in an English patent, in 1846. He steeped raw Gutta- 
percha, cut into small pieces, in a solution of caustic alkali or 
chloride of lime, to neutralize the acidity and remove any unpleas- 
ant odor. His experiments showed that the alkaline treatment 
not only reduced the percentage of dirt — that is, it was better 
cleaned than by the mechanical process — but lessened the capacity 
of the Gutta-percha for retaining mechanically enclosed water. 
But the treatment with chemicals requires great care and judg- 
ment, and thorough subsequent washing with water; otherwise 
the material will be rendered perishable. 

Chemicals were also used by Obach for hardening Gutta- 
percha. The really valuable constituent of Gutta-percha being 
the gutta, the more a sample contains of the latter, the better it is, 
provided the gutta itself is of a good description. For certain 
purposes it is advantageous to improve the hardness and other 
mechanical properties of Gutta-percha, and this can be done by 
extracting the resin with a suitable solvent, which leaves the gutta 
itself intact. The raw Gutta-percha is first chopped and thrown 
on drying platforms gently heated from below by steam pipes. 
Or the pieces may be thrown into a rotating drum heated by cur- 
rents of warm air. They then go to a series of tanks in which 
petroleum spirit is used as a solvent for the resin. The spirit 



GREEN GUTTA-PERCHA. 283 

becomes charged with the resinous matters, and the resulting 
solution is distilled off, after which the material remaining is 
masticated as in the case of any other Gutta-percha. A specimen 
treated by this process will remain quite hard under a temperature 
which will render other specimens soft and plastic. Other liquids 
may also be used, as ether, and a saturated solution of carbon 
disulphide in alcohol. 

Instead of removing impurities from Gutta-percha by wash- 
ing it either with water or an alkali, this can be done by dissolving 
the material into a suitable liquid, straining or filtering the solu- 
tion, and then evaporating the solvent. Carbon disulphide has 
been used as the solvent, but with the effect of rendering the 
Gutta-percha perishable. 

Recently an article known as Green Gutta-percha has been 
offered to the trade, being extracted from the leaves of the trees. 
Several systems for extracting Gutta-percha from leaves have 
been described. That of Dieudonne Rigole involves the use of 
carbon disulphide ; that of Eugene SeruUas the use of hot toluene 
as a solvent, after which the Gutta-percha is precipitated by 
means of acetone, instead of distilling off the solvent ; and that of 
Obach the use of light petroleum spirit as a solvent for leaves 
that have been previously crushed between rollers, the gum being 
reprecipitated from the solution on cooling below 60° F. The 
author of each process has devised apparatus for its operation. 

Many trees produce gums which have been experimented 
with in the hope that they would prove good substitutes for Gutta- 
percha, but none have proved of value except the "bullet" tree, 
which yields Balata. The gutta contained in Balata is very strong 
and tough, being of excellent quality ; but the percentage of resin 
is large, and the material can be regarded as a substitute only for 
second-class, or perhaps even third-class. Gutta-percha. Balata 
is somewhat more flexible than Gutta-percha containing an equal 
amount of resin, which appears to be due to the softness of the 
resinous constituents. On becoming heated Balata behaves much 
like ordinary Gutta-percha. If plunged into boiling water it 
becomes quite soft and plastic. If next immersed in cold water, it 
slowly hardens again, but still remains flexible and elastic, show- 
ing no signs of brittleness. Analyses of specimens of Balata from 



284 GUTTA-PERCHA. 

British Guiana, obtained from the London docks in 1889-94, 
showed an average loss of 13.8 per cent, of water, and 9.9 per 
cent, of dirt, or a total of 23.7 per cent, of waste. The respec- 
tive percentages of gutta and resin were 41.4 and 34.8. 

The specific gravity of cleaned Gutta-percha is practically 
the same as that of water, though varying with the relative pro- 
portion of gutta and resin, becoming lower as the percentage of 
resin increases. It may be affected, also, by the constitution of 
the resin and also of the gutta. The softening temperature of 
Gutta-percha depends entirely upon the ratio of gutta and resin. 
A specimen of which 60 per cent, was resin was softened at the 
temperature of 48° C. to the same extent as another specimen, 
containing only 2^ per cent, of resin, for which a temperature of 
55° C. was required. The time for the material to become hard 
again, after having previously been softened in hot water, depends 
in a like degree upon the proportion of gutta and resin. But the 
principal mechanical property of Gutta-percha with which the 
manufacturer has to deal is the tensile strength. A specimen hav- 
ing 45 per cent, of gutta and 55 per cent, of resin will break under 
pressure of 770 pounds to the square inch, whereas for another 
specimen, after most of the resin has been extracted with petro- 
leum spirit, nearly twice that breaking strain would be required. 
As for the elongation of Gutta-percha — i. e., the extent to which 
it will stretch before breaking — it is also affected by the percent- 
age of resin, being in the last two cases, for instance, 490 and 500 
per cent., respectively, but it also depends on the nature of the 
gutta. 

The earliest practical use of Gutta-percha was for surgical 
appliances — for bandages, splints, and receptacles for vaccine 
virus. It is used for ear trumpets; for the handles of surgical 
instruments, as it affords a firm grip and is preferable to wood 
for antiseptic reasons; in medicine, in the form (i) of a very 
thin tissue, (2) of sticks, and (3) of a 10 |>er cent, solution in 
chloroform; for chemical purposes, in the form of tubes, pumps, 
syringes, bottles, and the like, and for ladles and tubes for hand- 
ling caustic alkalies and corrosive acids and liquids in chemical 
works ; and for mechanical purposes, as rings and cups for pumps 
and hydraulic presses and for driving-bands (belting). For the 



USES IN INSULATION. 285 

latter purpose Balata is also used largely, interposed between can- 
vas ; such belts can be joined by means of a solution of Balata or 
Gutta-percha in carbon disulphide. Another application of Gutta- 
percha is that for taking impressions of medals, and also of the 
interior of large guns. Gutta-percha is also modeled into orna- 
ments in the shape of the leaves and petals of flowers, this being 
done by working the gum by hand in hot water with one or two 
simple iron tools. Such ornaments are often applied to the deco- 
ration of jars made of semi-porous ware, the whole being painted 
afterward. 

But the most important application of Gutta-percha is in the 
insulation of submarine and subterranean cables. Dr. Werner 
von Siemens first proposed Gutta-percha for insulating purposes 
in 1846, and in the next year he designed a screw-press, for the 
seamless covering of wires with that material, which is still in 
existence, while the principle of the press is still adhered to. Gut- 
ta-percha has been found to be very permeable to the X-rays, and 
it has been proposed to utilize this property to examine Gutta- 
percha-covered wires for the detection of defects in the copper 
conductor, particularly in "joints," or for finding air-bubbles. 
The X-rays may also be used for the detection of large foreign 
bodies in the raw Gutta-percha. Up to the end of 1907 no less 
than 248,000 miles of submarine cables had been laid, either 
commercial in character or government owned, embodying the 
use of Gutta-percha of a weight estimated at 32,000 tons. 
A further allowance must be made, for underground cables, street 
wires, etc., of 8,000 tons. The length of Gutta-percha-covered 
wires under the streets of London alone, some time ago, was 
17,000 miles, correpsonding to 375 tons of Gutta-percha. 

The electric properties of Gutta-percha depend chiefly on the 
nature of the gutta and to a less extent upon the resin; but only 
very slightly on the relative proportion of these two components. 
They depend also upon the nature and amount of the impurities 
and on the water. The insulation resistance and inductive capac- 
ity are little affected by the extraction of the resin. The insula- 
tion should be as high as possible, and the inductive capacity, 
for most purposes, as low as possible, but whereas the latter is 
mostly associated with other good qualities of the material, such 



286 GUTTA-PERCHA. 

is not always the case with a high insulation. A third electric 
property is called dielectric strength, or resistance to piercing by 
high voltages. A thickness of a little over ^ inch of Gutta-percha 
breaks down with 40,000 volts, and one of about i-ioth inch with 
28,000 volts. 

Gutta-percha hardened by the extraction of its resin is used 
chiefly in the manufacture of golf balls. Gutta-percha for this 
purpose should be tough, elastic, and not brittle at low tempera- 
tures ; it should be specifically lighter than water, in order not to 
sink if dropped accidentally into a ditch. It is requisite that the 
proper grade of raw material be chosen and that the resin be 
extracted as completely as possible. To test the elasticity of golf 
balls, a machine is used, consisting (i) of a perpendicular scale, 
divided into feet and tenths; (2) a clip, at the top, for holding 
the ball to be tested; and (3) an iron plate at the bottom. The 
object is to measure the rebound of the ball, when released from 
the clip and falling upon the plate. A ball made of Gutta-percha, 
of which 25 per cent, was resin, rebounded only to the point on 
the scale marked 30; a ball containing only 10 per cent, of resin 
rebounded to 45 ; and still another, having only a small percent- 
age, rebounded to 60 — the highest point reached. A ball of 
Balata, having the resin thoroughly removed, rebounded to 59. 

Some figures will give an idea how greatly the physical and 
mechanical properties of Gutta-percha are affected by the extrac- 
tion of the resin. Carefully selected specimens of a medium 
quality were cut fine and intimately mixed, and then divided into 
two portions. One portion was next washed in the ordinary way 
with water; the other treated with petroleum spirit until nearly 
all the resin had been extracted. The two specimens showed the 
following analyses : 

Gutta. Resin. Dirt. Water. Total. 
Cleaned in ordinary way 54.7 39.4 2.7 3.2 100 
Same material, hardened 93.0 2.8 2.5 1.7 100 

The different physical and mechanical properties of the two 

specimens are indicated in the next comparison : 

Ordinary. Hardened. 

Temperature when commencing to soften 37.7°C. S7.2°C. 

Temperature when commencing to harden s8.8°C. 9i.i°C. 

Time of hardening 17 min. 45 sec. 

Tensile strength — pounds per square inch 1592 5662 

Elongation — per cent 360 285 



CAUSES OF DETERIORATION 2^7 

The electrical properties, on the other hand, are but little 
affected, the insulation being practically the same as before, and 
the decrease of specific inductive capacity is probably due to the 
smaller percentage of water in the hardened material. 

The principal cause of the destruction of Gutta-percha is the 
absorption of atmospheric oxygen, which alters the gutta and pro- 
duces a brittle resin of quite a different nature to that originally 
present in the material. This destructive oxidization is greatly 
assisted by light, and by other causes — for instance, by any action 
tending to make the material porous, such as alternate wetness 
and dryness, the presence of substances which exercise a solvent 
action on Gutta-percha as a whole, or any of its components. 
Certain alkaline substances and decaying organic matters also 
appear to act injuriously, but frequently it is impossible to 
assign a definite cause for the decay of Gutta-percha. It is, how- 
ever, not merely manufactured Gutta-percha which undergoes 
these destructive changes, for raw material of the very best kind 
succumbs in time to the combined action of light and air. On 
the other hand, specimens of Gutta-percha are in existence which, 
after proper means of protection, have remained in good condition 
for more than fifty years. Complete immersion in water affords 
a good protection, for which reason submarine cores of Gutta- 
percha are more safely placed than underground wires. Another 
way of excluding the air, to some extent, is to varnish the Gutta- 
percha articles. When Gutta-percha is oxidized it becomes por- 
ous and full of cracks. If it be used for insulating wires, the 
insulation fails at such places, since the moisture perietrates the 
pores and fissures and establishes an electric contact with the 
conducting wire. 

Some compounds containing Gutta-percha are very useful 
for different purposes, and a specially useful one, consisting of a 
mixture of Gutta-percha, colophony, and Stockholm tar, is known 
as "Chatterton's compound." It is used largely in connection 
with the manufacture of Gutta-percha-covered wires, as a bind- 
ing material between the copper conductor and the Gutta-percha 
covering, or between the different layers of Gutta-percha on the 
core. 

Willoughby Smith patented the following compound for 



288 GUTTA-PERCHA. 

insulating wires : One-fifth by weight of Stockholm tar and about 
the same weight of resin are put into a vessel with a jacket (or, 
preferably, a series of pipes) heated by steam; when properly 
melted the whole is passed through a wire gauze strainer "into 
another vessel similarly heated" ; three-fifths by weight of Gutta- 
percha, having by preference been previously cleansed in the 
ordinary way, and reduced into thin pieces or shreds, is then put 
into the heated vessel and mixed with the resin and tar. In this 
second vessel are stirrers, for mixing the whole uniformly. 

Leonard Wray's cable compound was made of i part Gutta- 
percha, 4 parts India-rubber, 2 parts shellac, 2 parts flour of 
glass. This was used for underground wires. 

Gaullie combined Gutta-percha with Roman cement by means 
of animal gall, forming a plastic material, capable of being 
stamped and molded. 

Cooley mixed Gutta-percha with resin oil under heat, then 
mixed in carbonate of soda with roasted starch. To this com- 
pound he added asphalt to make it harder, or hyposulphite of lead, 
to make it softer. He also made a great many Gutta-percha com- 
pounds in which salts were present. These he steeped in water 
after mixing until they became soft and flexible. 

Charles Macintosh made a compound for telegraph wire 
from Gutta-percha, naphthaline, and lampblack. 

Charles Hancock boiled Gutta-percha in muriate of lime, 
passed it between heated cylinders, sifting the surface with rosin, 
in the production of a compound for complete insulation. An- 
other of his compounds was made of Gutta-percha, shellac, and 
borax. He also made Gutta-percha sponge by mixing with it 
carbonate of ammonia or alum and applying heat. He also made 
a hard Gutta-percha which was similar to vulcanite by mixing it 
with sulphur, putting it in molds and keeping the compound at a 
high temperature for several days. 

Duncan invented a great many compounds for Gutta-percha 
cement, many of which are now in general use. One suggestion 
of his was the mixing of Gutta-percha with Canada balsam and 
shellac, the resultant compound being a good cement capable of 
standing considerable heat and in no danger of becoming greasy 
on its surface. 



VULCANIZATION. 289 

Robert Hutchinson claimed that he was able to render Gutta- 
percha less liable to oxidize, to improve its elasticity, increase its 
tenacity, and diminish its liability to become sticky or tacky, by 
compounding it with lanichol or wood cholesterin. (See Lano- 
line.) Forster deodorized Gutta-percha by mixing with it essen- 
tial oil, orris root, or gum benzoin. 

Liquid Gutta-percha is Gutta-percha dissolved in chloroform, 
to which a little carbonate of lead is added in the shape of a fine 
powder. After agitation, the mixture is set aside until the 
insoluble matter has settled. The clear liquid is then decanted. 

Spill, in order to prevent Gutta-percha that had been vulcan- 
ized from being attacked by grease, treated it to a solution of 
melted beeswax, hardening this coating with an infusion of nut- 
galls. Godefroy mixed Gutta-percha with powdered cocoanut 
shell, claiming that it would stand a higher degree of heat, and 
was considerably more elastic. Day, in America, mixed pipe clay 
with Gutta-percha that is being vulcanized in order to prevent its 
sponging. 

The vulcanization of Gutta-percha, in spite of a common im- 
pression to the contrary, is something that can be easily accom- 
plished, and is analgous to the vulcanization of India-rubber. It 
can be done by mixing with free sulphur or sulphides that con- 
tain free sulphur, or by the use of chloride of sulphur. As the 
Parkes mixture attacks Gutta-percha very easily, the dipping for 
vulcanization must be very quick, the article being then allowed 
to remain in the air for some hours. The second dip can be a 
little longer, as the surface is less easily attacked than .before. The 
vulcanized product is quite hard and will stand a high degree of 
heat. Chloride of sulphur mixed with bisulphide of carbon can 
also be incorporated in a solution of Gutta-percha and bisulphide 
of carbon, with the result that the Gutta-percha will be thoroughly 
vulcanized. 

The late Robert Dick, of Glasgow, who was a successful 
manufacturer of Gutta-percha articles in the mechanical line, pro- 
duced many vulcanizable compounds of Gutta-percha of great 
value, some of which follow. He claimed that his compounded 
Gutta-percha retained the good qualities of the gum ; that is, that 
is was homogeneous and plastic at a moderate heat, but tough and 



290 GUTTA-PERCHA. 

hard at ordinary temperatures, and that it was just as valuable 
afterwards for mixing and molding over again. 

Compound No. i is described as the hardest and toughest, 
and may be used, in place of leather and vulcanized India-rubber, 
for tires, belts, pulley coverings, horse shoes, etc. No. 2 is softer 
and more elastic, and suitable for soles and heels of shoes, wringer 
rolls, springs, playing balls, mats, etc. These goods are mixed 
in the usual way, and vulcanize in the masticator, but not enough 
to take away the plastic qualities of the Gutta-percha. For treat- 
ing this compound, a special masticator was devised by Mr. Dick, 
the rolling cylinders being hollow, and a Bunsen gas burner 
inserted through one end of the hollow axle, while the gases pass 
off at the other, thus heating both roller and mixture. The outer 
cylindrical masticator is jacketed and heated with steam: 

COMPOUND NO. I. 

Pure cleaned hard Gutta-percha 28 

Pure cleaned tough selected Gutta-percha or Balata (preferably more 

rather than less) 11 

Pure cleaned "low white" Gutta-percha (preferably less rather than 

more) 9 

^'Crumb" or ground good old vulcanized India-rubber 34 

Hardwood veneer dust 5 

Sulphur 6i 

Zinc oxide (or zinc dust) 3i 

Flocking, or the cut fiber of cotton textile fabrics 3i 



Total 100 

COMPOUND NO. 2. 

Pure cleaned tough Gutta-percha 81 

Pure cleaned Balata or selected Gutta-percha 8i 

Pure cleaned "low white" Gutta-percha 24 

"Crumb" or ground good old vulcanized India-rubber :is 

Hard ground veneer dust 5 

French chalk, powdered 6 

Sulphur 6 

Zinc oxide (or zinc dust) 3 

Flocking, or the cut fiber of cotton textile fabrics 3 

Alum, ground 3 



Total 100 

Another compound patented by Mr. Dick embraced the use 
of low grade African and Borneo rubbers, which, after cleansing, 
were mixed with gutta-percha while still moist in hot water. 
After the mixing the compound is treated under a moist heat, 
where the temperature is 212° to 240° F., the result being a 



COMPOUNDS. 291 

tough, plastic, fibrous dough. This compound is then, so the 
inventor claims, equal to any service for which the Gutta-percha 
and Balata compounds are used. An important property in this 
compound is the shrinking quality which Gutta-percha possesses, 
while its power of cohesion rendered it especially valuable for 
insulating wires. 

Shepard mixed Gutta-percha with sulphur, exposed it to a 
heat varying from 300° to 350° F., admitting hot air, then com- 
bined it with sulphur and earthy matters. It was then vulcanized 
"by Parkes's cold curing process. 

Parkes dissolved Balata and mixed it with 5 per cent, of chlo- 
ride of sulphur, diluted with mineral naphtha. Gun cotton was 
also dissolved to a pasty mass, in naphtha distilled with chloride 
of calcium, and the two solutions were combined, forming a soft, 
flexible compound. 

Qiilds vulcanized Gutta-percha by mixing it with sulphur 
and placing it in a vulcanizer containing hydrated lime, and then 
turning on heat sufficient to obtain enough steam from the lime 
to do the curing. 

Duvivier and Chaudet treated Gutta-percha with bromide of 
sulphur or chloride of sulphur, making it more elastic and less 
liable to be acted on by heat or cold. When acid vapors were 
formed during the operation, carbonate of sodium was mixed 
with the solution. 

Rostaing made Gutta-percha hard and unalterable by treating 
it, after cleansing, with caustic soda, which was thoroughly 
washed out, after which it was combined with silicate of magnesia 
and treated with tannin, catechu, and other astringent matter. 

Keene cured Gutta-percha articles by exposing them to the 
fumes of sulphur or immersing them in a bath of melted sulphur. 

Charles Hancock treated Gutta-percha in a bath of boiling 
water in which was carbonate of potash, or muriate of lime, leav- 
ing it for an hour, and then mixing it with lead, glue, and bitu- 
men. His claim was that this treatment hardened the Gutta- 
percha, rendered it better adapted for bearing friction, and less 
likely to be oxidized. He also cured Gutta-percha by mixing 
with it sulphur, sulphides or orpiment, and applying heat. He 
gave as a compound for vulcanizing Gutta-percha 48 parts Gutta- 



292 GUTTA-PERCHA. 

percha, 6 parts golden sulphuret antimony, and i part sulphur, 
the compound to be boiled under pressure. 

Emory Rider mixed Gutta-percha with oxide of lead, heated 
it in open steam heat until the oily matters were expelled, then 
mixed it with hyposulphite of lead and cured it. 

Lucas prepared a printing roll of Gutta-percha, first immers- 
ing the Gutta-percha in nitric acid, and then placing it for an 
hour in a solution of carbonate of soda, thus producing a tougher 
wearing surface. 

Barlow and Forster mixed Gutta-percha with kauri gum 
and milk of sulphur for a cable coating. 

Macintosh immersed Gutta-percha in concentrated sulphuric 
acid for a number of seconds to harden the surface. He also 
mixed Gutta-percha with gun cotton, curing with sulphuric acid, 
claiming that the resultant compound was not likely to be affected 
by the heat of tropical climates. 

Analyses of common Gutta-percha, by Edouard Heckel and 
Fr. Schlagdenhauffen : 

Gutta 75 to 82 

Albane 19 to 14 

Fluavile 6 to 4 

Total 100 100 

Analysis by Payen: 

Gutta 78 to 82 

Albane 16 to 14 

Fluavile 6 to 4 

Total 100 100 

Gutta-percha is made of a mixture of hydrocarbons, and 

there is usually present a certain amount of oxygen. According 

to Granville H. Sharpe, F.C.S., its ultimate composition is : 

Carbon 86.36 

Hydrogen 12.15 

Oxygen 1.49 

Total 100. 

[Specific gravity, 0.96285 to 0.99923.] 

The primary analysis of Gutta-percha by Sharpe is: 

Hydrocarbon 7970 

Resin 15.10 

Wood fiber 2.18 



ANALYSES. 293 

Water 2.50 

Ash 0.52 

Total 100. 

Obach gives the following average results from a large num- 
ber of analyses of each of twelve leading brands or sorts of Gutta- 
percha : 

Gutta. Resin. Dirt. Water. 

Pahang 78.1 19.2 1.5 1.2 

Banjer red 67.0 30.2 1.5 1.3 

Bulongan red 68.6 29.0 1.4 i.o 

Bagan 57.5 40.9 i.o 0.6 

Goolie red soondie 55.2 42.9 1.2 0.7 

Serapong 56.2 42.4 0.9 0.2 

Bulongan white 52.2 45.4 1.5 0.9 

Mixed white 49-8 474 i-i i-7 

Banjer white 51.8 44.1 1.8 2.3 

Sarawak mixed 55.6 40.9 1.8 1.7 

Padang reboiled 50.3 45.8 2.0 1.9 

Banca reboiled 46.8 51. i i.i 1.0 

Another series of analyses by Obach relates to the constitu- 
tion of the resins in Gutta-percha, as follows : 

Albane. Fluavile. 

Carbon 78.76 80.79 

Hydrogen 10.58 11.00 

Oxygen 10.46 8.21 

Total 100. 100. 

Some typical Gutta-percha cement compounds follow: 

I. — For joining wood: Gutta-percha, 11 pounds; shellac, 3 
pounds; Venice turpentine, 5 pounds; pitch, i pound. 

2. — For uniting metals, glass, stone, and earthenware : Gutta- 
percha, 45 pounds ; shellac, 20 pounds ; gum mastic, 5 pounds ; 
oxide of lead ^ pound ; storax, 3 pounds ; Venice turpentine, 26-|- 
pounds. 

3. — For cementing leather : Gutta-percha, 4 ounces ; bisul- 
phide of carbon, 20 ounces ; asphaltum, i ounce ; common resin, 
I ounce. 

4. — Gutta-percha glue: Gutta-percha, i pound; rosin, i 
pound ; litharge, i ounce ; powdered glass, quantum suMcit. 

5. — Shoemaker's wax : Melt Gutta-percha, 20 ounces ; add 
pitch, 58 ounces ; soap, 5 ounces ; rosin, 6 ounces ; beeswax, 5 
ounces ; palm oil, i ounce ; tallow, 5 ounces. 

6. — For preserving metals and other surfaces : Coal tar, 20 



294 GUTTA-PERCHA. 

pounds; Gutta-percha, 5 pounds; minium, 6 pounds; white lead. 
7 pounds; pitch, 10 pounds; resin, 10 pounds; spirit turpentine, 
4 pounds; sulphur, 38 pounds. 

7. — General cement : Make a solution of Balata of 5 ounces 
in i gallon naphtha, and another of Gutta-percha 5 ounces in ^ 
gallon naphtha. Combine the two solutions and add 13 ounces 
resin or pitch and stir and mix thoroughly. 

"Gentsch's Gutta-percha" is a widely used substitute for 
Gutta-percha, made in general as follows : The ingredients used 
are mineral wax, tar, resin, and rubber. The process is thus 
described by a scientist who visited the English factory : A mix- 
ture of resin, wax, and tar was thrown into a kneading machine, 
steam being applied from below, to keep the temperature at the 
proper point. Twenty minutes later, the mass having been 
kneaded meanwhile, the steam was turned off and the rubber 
(cut into small pieces) added, being fed in slowly to prevent 
jamming of the knives of the kneading machine. The machine 
was stopped from time to time to test the condition of the mass, 
and at the end of three hours the solution of the rubber was 
found to be complete and the mass was removed from the machine 
and passed between rollers, coming out in slabs ^ inch thick — 
the finished material. 

THE ANALYSIS OF GUTTA-PERCHA. 

This of course refers to the analysis for the crude gum, and, 
to have the analysis complete, it should cover the amount of water 
present, the amount of foreign matters and impurities, the amount 
of ash, the amount of pure gutta, and the amount of resins. 

The water is easily determined by heating a known weight 
from the sample at a temperature ranging from 212° to 230° F., 
the loss in weight being the amount of water present. This is a 
common process in chemical analysis. In the case of Gutta- 
percha, it must be varied, as the sample is liable to oxidize even 
under examination, causing an increase of weight. This is over- 
come by conducting the heating in a slow current of nitrogen, or 
carbonic acid gas. 

J. A. Montpellier devised an apparatus for this, which con- 
sisted of a special retort with a large opening which he used as a 



ANALYSES. 295 

vapor bath and having a tubiihire at its side. It is closed by a 
large cork, in which there are two holes, one for the tube which 
is to introduce the gas, and the other for the thermometer. The 
sample to be dried is placed in a crucible of porcelain or platinum 
suspended within the retort. As the water evaporates it is borne 
by the current of gas through a tube inserted in the side tubulure, 
and into U-shaped tubes, containing sulphuric pumice, which 
retain it. Further on the U tubes are connected with a Liebig 
tube with five bulbs containing pure sulphuric acid preventing 
the entrance of moist air after the apparatus cools, a further use 
being to make it possible to regulate the speed of the current of 
gas. 

The retort is immersed in an oil bath heated by a Bunsen 
burner. If carbonic acid be used it is obtained by the action of 
hydrochloric acid on marble chips produced in a Kipp apparatus 
followed by wash flasks, the first of which contains bicarbonate of 
potassium in solution, which is intended to stop the passage of 
any hydrochloric acid, and the second containing sulphuric acid at 
150° to thoroughly dry the gas. To be absolutely sure that this 
gas is dry a dessicator filled with sulphuric pumice is placed 
between the retort and the second wash flask. The operation of 
drying one gram with this apparatus takes 6 or 7 hours. The 
determination of the amount of impurities, which comes next, may 
be effected very easily, by using M. F. Jean's exhaust apparatus. 
A small part of the sample, from one-half a gram to a gram, is 
weighed, cut into small fragments, put in a filter, the weight of 
which is known, which in turn is placed in a platinum cone. This 
cone is then put in the extension of the apparatus ; this extension 
communicates by two tubes with the retort containing pure chlo- 
roform. A condenser, in which a current of cold water con- 
stantly circulates in order to condense the chloroform vapor, is 
placed at the upper part of the extension. 

The retort rests on a sand-bath, very gently heated by a Bun- 
sen burner. Under the influence of the slight heat the chloroform 
evaporates, passes through one of the tubes, and drops on the 
filter containing the Gutta-percha, which it gradually dissolves. 
The solution, passing through the filter, then drips into the retort 
through the second tube. 



296 GUTTA-PERCHA. 

All the impurities remaining in the filter, it is sufficient to 
dry and weigh the filter to get the weight of the foreign matters, 
the drying should be done in the apparatus used in determining 
the amount of water. 

The next process is the determination of the amount of ash. 
In Gutta-percha this is always very small, as mineral matter is 
almost entirely absent from it, the quantity never exceeding one- 
half of I per cent. The amount of ash is determined by burning 
in a capsule of platinum or porcelain a known weight of Gutta. 

The fourth step is the determination of the amount of pure 
gutta, and of the resins. Both fluavile and albane are soluble in 
absolute alcohol at the boiling point, and as pure gutta is insoluble 
in it, this is a very ready means of separation. The sample to 
be examined is cut in little bits, put in a platinum basket which is 
pierced with holes, and hung in a retort containing the alcohol. 
This retort is heated with a sand-bath or water bath, the vapor 
of the alcohol passing through a Liebig condenser and returning 
to the retort. The boiling is continued for 5 or 6 hours, with 
the basket immersed in the alcohol. It is then raised above the 
liquid, and the boiling continued for 5 or 6 hours more. The 
latter part of the process removes the last traces of resin. 

The boiling operation being completed, the pure gutta to- 
gether with the impurities remains on the filter. There remains 
then the drying of the filter in the apparatus used in determining 
the amount of water and the weighing of it. The loss of weight 
shown by the Gutta-percha corresponds to the amount of resins 
increased by the weight of the water. Subtracting that weight, 
already determined, the weight of the resins remains. 

Wilton G. Berry, Ph.B., is the author of a monograph on the 
analysis of Gutta-percha resins, the basis of which was a paper 
read before the Society of Chemical Industry. In it he dealt with 
the comparative quantitative analyses by treatment of the pre- 
viously dried material with acetone, alcoholic-potash, and petro- 
leum ether, and extraction of the resins in a uniform manner 
with boiling absolute alcohol, and the separation of the thus ex- 
tracted resins into their component resins, soluble and insoluble 
in cold absolute alcohol. 

The object was the determination of — 



ANALYSIS OF RESINS. 297 

Saponification value. 

Acid value. 

Ether value. 

Iodine value, 

Acetyle value, 

Methyl value, 

Melting point, solubility, etc., 

— of the individual resins, hoping thus to establish a table of 
values w^hereby the resins of any given specimen may be iden- 
tified and the identity of the parent gum thus established. The 
gums thus far experimented on are a few specimens each of 
Gutta-percha, Chicle, Almeidina, Tuno, Jelutong (Pontianak), 
Balata, and Payena sp. 

It has been found thus far that the resins from several speci- 
mens of the same gum have practically the same constants and 
characteristics, and that the resins from the different species of 
gums have different constants and characteristics — in some widely 
different, and in the cases of the gums above cited sufficiently 
differing to make identification of their parent gum an easy 
matter. From the gums so far examined it is hoped to establish 
the fact that the combined evidence of the constants and charac- 
teristics of the resins, together with the character of the accom- 
panying hydrocarbons, will show that each species of gum varies 
from each other sufficiently to make differentiation of unnamed 
specimens complete, and to establish the fact that every specimen 
of the same species of gum is alike in the characteristics quoted. 

RESUME OF ANALYTICAL WORK. 

Gutta-percha. — Resins soft, pasty, yellow. 

Chicle. — Resins hard, grayish yellow, brittle. 

Tuno. — Resins hard, dark yellow, brittle. 

Almeidina. — Resins hard, brittle, yellow. 

Jelutong. — ^Resins soft, brittle, yellow. 

Balata. — Resins turbid liquid, yellow. 

Payena. — Resins similar to Chicle resins. 

Saponification value. Acid value. 

*Gutta-percha resins . 78.5 5 

*Gutta-percha (albane) 83.5 — 

*Gutta-percha (fluavil) 71.45 — 

*Chicle resins 103. i Trace 

Chicle (resin A) 129.0 Trace 

Chicle (resin B) 100.8 Trace 

fTuno resins 77.3 5.6 

tjelutong 77.5 Trace 

Almeidina S0.4 ii.o 

Balata 69.2 Trace 

fPayena sp 103.7 Trace 

* Average of 4 specimens. t Average of 2 specimens. 



2^ GUTTA-PERCHA. 

While the saponification values of Gutta-percha, Tuno, and 
Jelutong resins respectively are almost identical, their separation 
into component resins corresponding to albane and fluavil of 
Gutta-percha gives entirely different results from the latter and 
from each other. The resins of Chicle and Payena differ ts 
widely and the accompanying hydrocarbons are quite different. 

BALATA. 

Balata is the gum of the "bully" or "bullet" tree — the 
Mimusops balata — found in British and Dutch Guiana, and in 
Venzuela. It is marketed in two forms, "block" and "sheet." The 
sheet is usually worth about 30 per cent, more than the block 
Balata, The sheet is used for belt covering, while the block is 
more used in compounding. Balata is usually reddish gray, 
though sometimes brown. The dried sheet milk or sheet product 
usually contains 39 per cent, gutta and 37 per cent, rosin; while 
the boiled or block contains 51 per cent, gutta and 48 per cent, 
rosin. The sheet shrinks from 10 to 20 per cent, while the block 
shrinks from 20 to 30 per cent. 

The balata tree may be tapped when 5 inches in diameter. If 
tapped too deep, the tannin sap injures the product, and the 
wound is slow to heal. The outer bark is removed before tapping. 
The milk runs for about three hours, and a tree will generally 
yield about 3.6 liters of milk, or i^ to 2 kilos of Balata. It 
usually requires about two weeks for the milk to dry. 

In character this gum occupies a position between India- 
rubber and Gutta-percha, combining in a degree the elasticity of 
one with the ductility of the other, and freely softening and 
becoming plastic and easily molded in hot water. Balata is dried 
ordinarily by evaporation. A more rapid coagulation is effected 
by the use of spirits of wine. Alum is sometimes used to coagu- 
late, but is not very satisfactory. The gum is sometimes mixed 
during the gathering with the milk that produces gum known as 
Touchpong and Barta-Balli. It is used principally in the manu- 
facture of belting and for insulation work. It has been utilized 
also for golf balls and as a substitute for rubber in dress shields. 

MuRAC is a commercial product resulting from the treat- 
ment by a chemical process of the latex of certain plants of the 
Sapotacece family, as Balata, for example. Made in England. 



INDEX. 



AsBA rubber 42 

Abies halsamea 154 

Abyssinian gutta 42 

Accra rubber 25 

Acetate of lead 79 

Acetic acid 36, 189 

Acetone 224 

Achras sapota 45 

Acid, Acetic 36, 189 

Boracic 192 

Carbolic 193 

Chromic 197 

Citric 197 

Formic 27> 198 

Hydrochloric 199 

Mimo-tannic 200 

Muriatic 200 

Nitric 200 

Oleic 201 

Oxalic 201 

Phenic 193 

Phosphoric 202 

process of reclaiming rub- 
ber 14s 

proof composition, Just's. 13S 

Pyroxylic 238 

Salicylic 203 

Stearic 204 

Sulphuric 205 

Tannic 205 

Tartaric 206 

Tungstic 206 

Acids, alkalies, and their deriva- 
tives 189 

Action of metals on rubber 253 

Adamanta no 

resin 151 

Addah niggers 25 

Adhesive, renderng rubber 255 

Adhesor 1 10 

Adirondackite no 

African rubbers. List of 21 

Shrinkage of 257 

Agalmatolite 79 

Air-brake hose, testing 261 

Albane 277 

Alcohol as a solvent 224 

Ale 189 

Alexite 125 



Algm gum 1 10 

Alkalies and their derivatives... 189 

Allard's fireproof felt 247 

Almeidina rubber 42 

Alstonia plumosa 50 

Alum 190 

cure 71 

in coagulation 36 

Alumina, as a filler 80 

Sulphate of 204 

Aluminum flake 79 

lanolate 207 

Oxide of 95 

Aluminite 79 

Alundum 80 

Amazonian resin rubber 43 

Amber 151 

Burmite 154 

Oil of 216 

resin substitute iii 

Ambriz rubber 27 

Ambroin 125 

Ammonia 190 

Carbonate of 194 

Caustic 195 

Hydrochlorate of 198 

Muriate of 200 

Tungstate of 206 

Ammoniacum, Gum 159 

Ammonium, Chloride of 196 

Amole juice 35 

Amorphous sulphur yi 

Amphiboline 80, 248 

Analysis of oil substitutes log 

Analysis of gutta-percha 292, 294, 296 

lampblack 179 

rubber compounds 267 

rubber substitutes 269 

vulcanized rubber 260 

Angostura rubber 16 

Anhydrite 80 

Anhydrous paraffine oil 207 

Aniline 191 

colors 173, 241 

Anilines in coloring rubber 172 

to be avoided 173 

Animal charcoal 86 

oils in rubber compounds 207 

substances in dry mixing. . ro6 

299 



30O 



INDEX 



Anime, Gum 158 

Anthracine 226 

Antimony 80 

Black 83 

Crimson sulphide of 184 

Grolden sulphuret of 7:^ 

Golden sulphuret of, red . . 74 

in curing rubber 67 

Iodide of 199 

Oxide of 95 

Penta-sulphide of 75 

Anti-poison act, German 175 

Antipolo gum 43 

ApocynacecB 7 

"Apo elastikon hyphasma" 133 

Arabic, Gum 158 

A. R. D. gum Ill 

Argillaceous red shale 80 

Armalac 125 

Arsenate of potash 191 

Arsenic as a filler 80 

yellow 186 

A rtemisia absinthium 216 

Artificial asphalt 152 

elaterite iii 

Gutta-percha iii 

India-rubber (Fenton's) .. 114 

rubber milk 254 

sulphuret of lead 71, 80 

whalebone 125 

ArtocarpecB 7 

Artocarpus Kunstleri 45 

Aruwimi rubber 27 

Asbestic 81 

Asbestine 81 

Asbestonit 133 

Asbestos 81 

AsclepiadacecE 7 

Ash, Bone 84 

test of rubber substitutes . . 270 

Asphalt 151 

Mineral India-rubber 163 

Trinidad 170 

Asphalte, French 157 

Asphaltum, Gum 159 

Assam rubber 29 

Assinee rubber 24 

Astrictum 133 

Atmido 82 

Atmoid 82 

A ttalea excelsa 35 

Attoaboa rubber 24 

Aureolian yellow 186 

Australian caoutchouc 45 

Auvergne bitumen 152 

Axim rubber 25 

Ayling's cold cure 69 



Baka gum 43 

Bakelite 126 

Balata 298 

as a substitute for Gutta- 
percha 283 

tree 283 

Balenite 126 

Ball, African 22 

Balloons, dyeing 172 

Balsam 152 

Canada 154 

of storax 152 

of sulphur 153 

Sulphur 76 

Tolu 171 

Balsams in rubber compounding 151 

Banana rubber 44 

process for extracting . . . 256 

Bangui rubber 26 

Banigan's (Joseph) experiments 68 

Barberry yellow 186 

Barium chloride 191 

sulphide 72 

white 174 

Barrel lining, Zinsser's 138 

Barta-Balli gum 44 

Bartyes as a filler 83 

Baryta, Carbonate of 85 

Baschnagel's devulcanizing pro- 
cess 145 

Bassia Parkii 47 

Bastard or pseudo gums 41 

Batanga ball 25 

Bathurst rubber 24 

Bayin rubber 24 

Beckton white 174 

Beeswax 153 

Beira rubber 44 

Belgian Congo, rubber from ... 26 
Belledin's process for leather 

impregnation 134 

Bell (P. Carter) on analyses of 

rubber 267 

Belting, rubber. Tests of 266 

Benguela rubber 27 

Benin ball rubber 25 

Benzoin, Gum 159 

Benzol 226 

Nitro-benzol 235 

Benzole 226 

Beta separator 36 

Berry's (W. G.) analysis of 

gutta-percha resins 296 

Beverley Rubber Works 145 

Beylikgy's devulcanizing process 147 

Biborate of soda 192 

Bichromate of potash 192 



INDEX 



301 



Birch bark tar 153 

oil 207 

Biscuit rubber 22,, 33 

Bismuth rubber cure 67 

Bisulphate of potash 192 

Bisulphide of carbon 227 

Substitute 227 

Bitite 126 

Bitumen 153 

Auvergne 152 

Black antimony 83 

dye for rubber 239 

German substitute 1 1 1 

hypo 83, 180 

lead 83 

Mineral 179 

Oak 180 

pigments for rubber 178 

pitch IS4 

Blacks, Carbon 180 

Blandite 1 1 1 

Bleaching powder 192 

Block rubber 33 

Blown oils 208 

Bkie, Chrome 182 

Cobalt 182 

Indigo 182 

lead 83 

Molybdenum 182 

pigments 180 

Prussian 182 

Saxon 182 

Thenard's 182 

Yale 181 

Boot and shoe manufacture .... 54 
Bolas (Thomas) on shrinkage of 

rubber 256 

Bolivian rubber 15 

Bone ash 84 

black 84, 179 

naphtha 231 

oil 208 

Boracic acid 192 

Borax 192 

as a solvent 227 

Borate of zinc 174 

Borcherdt's compound iii 

Bordeaux turpentine 235 

Borneo rubber 29 

Bosanga 36 

Bougival white 174 

Bourn's (A. O.) devulcanizing 

process T46 

Brimstone, Gold 73 

British gum 154 

Bromine rubber cure 72 

Bronzed appearance on rubber . . 24c 



Brooksite 126 

Brosium galactodendron 46 

Brown pigments 183 

Brown's substitute 127 

Bucaramanguina 84 

Bumba rubber 27 

Burgundy pitch 154 

Burmite amber 154 

Burnt umber 84 

Bussira rubber 2y 

Button lac 154 

Buttons, rubber 23 

Butyrospermum Parkii 47 

Cadmium yellow 185 

Cake rubber 24 

Calamine 84 

white 175 

Calcium, Chloride of 196 

white 84 

Calendering rubber 61, 63 

Calomel 85 

Calotropus giganticus 49 

Cameroons rubber 25 

Cameta rubber 14 

Camphene 228 

Camphor 228 

Gum 159 

oil 208 

Canada balsam 154 

Candle tar 154 

Canoe gums 44 

Canvas sails, waterproofing .... 247 

Caoutchene 112 

Caoutchite 133 

Caoutchouc aluta 127 

Caoutchoucine 228 

Caoutchouc oil 208 

Cape Cattimandu 44 

Cape Coast rubber 25 

Carbolic acid 193 

Carbonaceous clay 85 

Carbonate of Ammonia 194 

baryta 85 

lead 85 

soda 194 

zinc 175 

Carbon blacks 180 

Bisulphide of 227 

Chloride of 230 

Substitute 227 

tetrachloride 228, 237 

Carbo-nite 112, 127 

Carburet of iron 85 

Carnauba wax 155 

Carn gum 155 

Carpodinus lance la tus 50 



302 



INDEX 



Carriage cloth manufacture 57 

Carrol gum H2 

Cartagena rubber 18 

Casein I5S 

Caseum 155 

Castilloa elastica 11 

Castor oil 208 

Catechu 195 

Cativo gum 44 

Cattell's process for deodoriza- 

tion 248 

Cattimandu gum 44 

Caucho I5> i6 

Caulbry's rubber cure 71 

Caustic ammonia I95 

potash 195 

soda 194 

Caviana rubber 13 

Ceara rubber 18, 34 

Cellit 140 

Cellulith 141 

Celluloid 140 

Potato 131 

Rubber, Luffs 136 

Cellulose 141 

Compound 142 

nitro 141 

Cement manufacture 60 

compounds. Gutta-percha. 293 

Davy's universal 166 

Portland 99 

Theskelon 137 

Cements, Rubber 222 

Coloring I73 

Centrifugal method of coagula- 
tion 36 

Central American rubber 17 

Shrinkage of 257 

Ceramyl IS5 

Cerasin I55 

Cereal rubber 112 

Ce-re-gum 127 

Ceresine I55 

Ceylon rubber 30 

Chapel (E.) on shrinkage of 

rubber 258 

Chalk as a filler 85, 104 

French 90 

Red 100 

Charcoal animal 86 

vegetable 86 

Charlton white I7S 

Chatterton's compound 127, 287 

Chemical process of reclaiming 

rubber 143 

Chemical Rubber Co 145 

Cherry gum 155 



Chicle gum 45 

substitute 112 

China clay 87 

Chinese wood oil substitute 112 

Chloride, Barium 191 

Chloride of ammonium 196 

calcium 196 

carbon 230 

lime 196 

sodium 196 

sulphur rubber cure 70, 7-5 

zinc 197 

Chlorine, Liquid 75 

rubber cure 69 

Chloroform 230 

Cholesterin 209 

Christia gum 113 

Chrome blue 182 

green 187 

yellow 187 

Chromic acid 197 

Chute's rubber resin solvent 231 

Citric acid 197 

Clapp's (E. H.) devulcanization 

patents 145 

Clay, Carbonaceous 85 

China 87 

Cornwall 87 

Fire 89 

Pipe 98 

Clothing manufacture, Rubber.. 57 

Coagulation of rubber 35 

Coalite pitch 156 

Coal, Powdered 100 

Coal tar 156 

naphtha 233 

Coarse Para rubber 13 

Cobalt, Blue 182 

Codliver oil 209 

Cod oil 209 

Colcothar 184 

Cold curing process 69 

Colombian rubber 18, 31 

Colophane 156 

Colophony 156 

Color of rubber. Natural 172 

Colored design for proofed fab- 
rics 241 

Coloring rubber 172 

rubber surfaces 174 

Colors, Black 178 

Blue 180 

Brown 183 

for admixture with rubber 241 

Green 187 

Red 183 

White 174 



INDEX 



y»i 



Colors, Yellow 185 

Colza oil 209 

Compo 87 

Composition, Just's acid proof... 135 
Compounding rubber, Reasons 

for 79 

Compounds for showerproofing. . 243 

Borcherdt's iii 

Chatterton's 127, 287 

Congo Free State 26 

Doebrich's 113 

Ireson's packing 135 

Jackson's 135 

Johnstone's non-drying . . 135 

Jungbluth's 116 

Kiel 129 

Kirrage 136 

Leatherubber 136 

oil 217 

Roland's puncture 140 

rubber 26 

Sorrel's 131 

Weber's cellulose 142 

Wray's 133 

Con-current rubber 113 

Consolidated oil 209 

Coorongite 45, 156 

Copal, Gum 160 

Copper, effect of on rubber 254 

Sulphate of 204 

Coralite 127 

Cork 87 

Corkaline 113 

Cork leather 133 

Cornite 127 

Corn oil 209 

substitute 113 

Cornwall clay 87 

Corundum 87 

Corypha cerifera 155 

Cost of rubber after shrinkage . . 258 

Costtis afer 36 

Cotton gun 141 

silicate loi 

Cottonseed oil 209 

Coutinho's machine 36 

Cow tree rubber 46 

Coyuntla juice 36 

Crape cloth 247 

Cravenette process 243 

Cream of tartar 198 

Creosote oil 210, 230 

Crepe rubber ZZ 

Crimson sulphide of antimony . . 184 

Crystals of soda 198 

Cumai rubber 46 

Cutch 195 



Cyanide of potassium 198 

Cyco 139 

Dammar, Gum 160 

Danin's machine 37 

Dankwerth's Russian substitute. 113 

Davy's universal cement 166 

Day, Austin G., rubber substi- 
tutes 62 

Day, Horace H., early rubber 

manufacture 68 

De Pont substitutes 127 

Deodorization of rubber 106, 248 

Dental rubber 60 

Dermatine 134 

Devulcanization of rubber 143 

Dextrine 1 56 

Dextrose 156 

Diatite 127 

Diatomaceous earth 88 

Dichlor-ethylene 231 

Dichopsis elliptica 50 

Dichopsis polyantha 279 

Dieffenbach's (George) rubber 

cure 67 

Dippel's oil 231 

Divisions of the rubber manufac- 
ture 53 

Doebrich's compound 113 

Dow's inner tube filler 139 

Druggists' sundries manufacture 55 
Dry-heat test of rubber substi- 
tutes 269 

Drying oils in rubber substitutes 198 

Drying rubber 62 

Dry mixing 79 

Durango rubber 46 

Durate 134 

Dutch Congo ball 26 

pink 187 

Dyera costulata . 50 

Earth, Diatomaceous 88 

Fuller's 90 

Infusorial 90 

wax 156 

Earth waxes in rubber com- 
pounds 151 

East India rubbers 29 

Shrinkage of 258 

Eaton's (A. K.) rubber cure 67 

Ebonite 128 

Ekanda rubber 27 

Ekert's high pressure composi- 
tions 134 

Elasteine 113 

Elastes 138 



304 



INDEX 



Elasticate II4 

Elastic glue I14, 157 

Elasticum, nigrum 118 

Elastite 114 

Elaterite 114, 156 

Artificial iii 

Electric facing 88 

Electrose 127 

Elemi, Gum 160 

Elmer's (William) rubber cure.. 70 

Embossing rubber 240 

Emery 88 

Endurite 134 

Equateur rubber 26 

Esbenite 128 

Esmeralda rubber 18 

Essence of petroleum 210 

Ether as a solvent 231 

Eucaliptia 210 

Eucalyptus globulus 210 

Eucalyptus oil 210 

Eucturbe edulus 35 

Euphorbia fulva 50 

rhipsaloides 43 

tirucalli 43 

trigona 44 

Euphorbia rubber 46, 114 

EuphorbiacecB 7 

Euphorbium, Gum 160 

Everlastic 139 

"Excelsior," reclaimed rubber .. 113 
Extract test of rubber substitutes 269 

Facing, Electric 88 

Fagioli 139 

Falke's (Oscar) rubber cure 67 

Fard's Spanish white 175 

Farina 88 

Fossil 89 

Test for 275 

Fastening rubber to metal 251 

Faure's devulcanizing patent . . . 143 

Fayolles' substitute 114 

Feldspar 88 

Fenton's artificial rubber 114 

Fiber, Lamina 130 

Vulcanized 132 

Fibers in rubber mixing 105 

Fibrine-christia gum 134 

Fibrone 128 

Fichtelit 157 

Ficus elastica 12, 34 

obligua 44 

Vogelii 42 

Fig Juice roofing 115 

Filler, Bow's inner tube 139 

Suber's 140 



Fillers in dry mixing 79 

Fine Para rubber 13 

Fire clay 89 

Firmus 115 

Fish glue 157 

oil 210 

Flake, aluminum 79 

rubber 23, 2)i 

Flint 89 

Liquid of 200 

Flour of glass 89 

Marble 94 

Mountain 95 

phosphate 89 

Wheat 103 

Fluoride of silicon 198 

Fluvia gum 46, 50 

Formic acid 198 

in coagulation ^y 

Forsteronia gracilis 48 

Fossil farina 89 

meal 90 

Frankenberg's waterproof cloth. 247 
Frankenburg's puncture fluid . . 139 

Frankincense, Gum 160 

Franklin substitute 115 

French asphalte 157 

chalk 90 

Congo rubber 25 

Gutta-percha 115 

Navy tests of rubber belt- 
ing 266 

talc 103 

West Africa 23 

wool grease 211 

Frost rubber 134 

Fuller's earth 90 

Fulton white 175 

Fumero $7 

Funtumia elastica 12, 39 

Gaboon rubber 25 

Galalith 141 

Gambia rubber 24 

Gamboge gum 160 

yellow 186 

Gambria gum 50 

Garnet lac 157 

Garnier's (Edmond) alum cure.. 71 

rubber shellac mixture 77 

Gas, effect of on rubber 252 

obtained from rubber 252 

tubing, manufacture of . . 253 

Gasoline 231 

Gelatine, Glugloss 158 

Genasco hydro-carbon 138 

Gentsch's gutta-percha 294 



INDEX 



3^5 



German substitute, black iii 

Gilbert-Besaw devulcanizing pro- 
cess 148 

Gilsonite 157 

Glass, flour of 89 

Soluble 204 

Glucose 157 

Glue 158 

Elastic 114, 157 

Fish 157 

Waterproof 124 

Glugloss-gelatine 158 

Gluten 158 

Glycerine in rubber compounds. 211 

Goa gum 46 

Gold brimstone 73 

Gold Coast rubber 24 

Gold leaf applied to rubber 240 

Gold, Oxide of 96 

Gk>lden sulphuret of antimony.. 73 

Golf balls 286 

Hard core for 128 

Goodyear (Charles) vulcaniza- 
tion process 66 

triple compound 105 

Gossypium herbaceum 209 

Grades of crude rubber 7 

Grand Bassam rubber 24 

Graphite 90 

Grape rubber 115 

Green, Chrome 187 

dyes for rubber 239 

Hungarian 188 

Saxon i88 

Gutta-percha 283 

pigments 187 

ultramarine 188 

Gregory & Thorn's devulcanizing 

process 148 

Greytown rubber 17 

Griffith's white 175 

Griscom's substitute 115 

Gront and Moore's repair ce- 
ment 134 

Guatemala rubber 17 

Guayaquil strip rubber 17 

Guayule rubber 19, 42 

Gubbin's devulcanizing process.. 148 

Gum Algin no 

ammoniacum 159 

anime 158 

Antipolo 43 

arabic 158 

A. R. D Ill 

asphaltum 159 

Baka 43 

benzoin 159 



Gum, British 154 

camphor 159 

carbon 115 

Carn 155 

Carrol 112 

Cherry 155 

chicle 45 

Christia 113 

copal 160 

dammar 160 

elemi 160 

euphorbium 160 

fibrine 115 

Fibrine-christia 134 

frankincense 160 

gamboge 160 

gambria 50 

Goa 46 

juniper 161 

Kauri 162 

lac 161 

lini 161 

Manila 163 

olibanum 161 

Rhea 120 

Spruce 169 

thus 162 

tragacanth 162 

tragasol 161 

turpentine 161 

Winthrop 124 

Xanthorrhea 171 

Gums used in rubber compounds 151 

Gun cotton 141 

Gutta Bassai 46 

Gutta-grek 47 

Gutta Horf oot 47 

Gutta-like gums. Refining 255 

Guttaline 116 

Gutta- jelutong 48, 50 

Gutta-percha, Chapter on 276 

Analyses of.. 277, 292, 293, 294 

Artificial in 

"Banjermassin" 278 

Brooman's patents 281 

cement compounds 293 

Chemical cleaning of, 280, 282 
Commercial classification 

of 278 

Components of 277 

compounds 290 

Deodorization of 248 

Deterioration of 287 

Dick's compounds 289 

Effect of heat on 276 

extracted from leaves 283 

French 115 



3o6 



INDEX 



Gutta-percha, Grades of 279 

Green 283 

Hancock's compounds, 288, 291 
Hancock's patents ....280, 282 

hardened chemically 282 

in compounds 287 

in golf balls 286 

in insulation 285 

Liquid 289 

"Macassar" 278 

masticator 281 

Mechanical cleaning of . . . 280 

mixing machine 281 

Montpelier's apparatus for 

analyzing 294 

Obach's analysis of . .279, 293 

Payen's analysis of 277 

percentages of waste 281 

Properties of 276 

Reboiled 279 

Resins in 277, 296 

slicing machine 280 

Smith's compound 133, 287 

Sources of 276 

Specific gravity of 284 

Substitutes for ...108, 116, 125 

"Sumatra" 277 

Uses for 284 

Vulcanization of 70, 289 

White . . . . ; 279 

Gutta-shea 47 

Gutta-sundek 280 

Gutta-susu 30, 48 

Gypsum 90 

Haf Jack rubber 24 

Halcox 116 

Hall's (Hiram L.) devulcanizing 

patents 145 

Hancock's Gutta-percha pat- 
ents 280, 282 

process for deodorization 

of rubber 249 

Hard core for golf balls 128 

Hard rubber substitute, KempeflF 129 

Hard rubber 125 

Decoration of 239 

manufacture 59 

Substitutes for 125 

Harmer's substitute 134 

Harris's (Charles T.) rubber 

cure 67 

Hatchetine 163 

Havemann's (R. F. H.) rubber 

cure 69 

Hay ward's vulcanizing patent . . . 145 

Heat in coagulation 37 



Heinzerling's devulcanizing pat- 
ent 146, 148 

Helenite 162 

Heifer process of coagulation . . 37 
Helm's (John, Jr.) rubber cure 69 

Hematite, Red 184 

Henriques (Dr. Rob.) analysis 

of rubber substitutes 271 

Testing rubber 267 

Heptane 231 

Herminizing process 67 

Hevea Brasiliensis 8, 11, 30 

Heveenite 135 

Heveenoid 135 

Heyl-Dia's devulcanizing process 149 

Honduras strip rubber 18 

Honeycomb sulphur 74 

Hose air-brake, Tests of 261 

Hungarian green 188 

Hyaline 128 

Hydro-carbon, Genasco 138 

rubber 116 

Hydrochlorate of ammonia .... 198 

Hydrochloric acid 199 

Hydrochlorite of lime 198 

Hydrogen, peroxide of 201 

Hydrolaine 116 

Hydrolene 212 

Hydrosulphuret of lime 198 

Hypo, black 83, 180 

Hyposulphite of lead 74 

Sodium 204 

Tdrialin (Idrialit) 162 

Impregnating rubber 243 

Indian red 184 

India-rubber compounds 79 

leather 135 

Substitutes for 108 

Indigo blue 182 

Infusorial earth 90 

Inrig 139 

Insolacit 128 

Insulite 1 16 

Insulated wire manufacture .... 59 

Insullac 128 

Iodide of antimony 199 

zinc 199 

Iodine 74 

I pomoea bona-nox 36 

Ireson's packing compound 135 

Iron, Carburet of 85 

pyrites 91 

rubber 129 

Isinglass 162 

Islands rubber 13 

Isolatine 129 



INDEX 



307 



Isoprene 232 

Itaituba rubber 14 

Jackson^s compound for printers 

rolls 135 

Japan wax 212 

Java rubber 29 

Jelly, Petroleum 217 

Jelutong 48, 50 

Jenkins's valve packing 91 

Jequie rubber 19 

Jeve rubber 48 

Jintawan rubber 48 

Johnson's non-drying compound 135 

Jones's substitute 116 

Joselyn's (Henry W.) rubber 

cure 68 

Jungbluth's compound 116 

Juniper, Gum 161 

Just's acid proof composition . . . 135 

Kamerun rubber 25 

Kamptulicon 135 

Kaolin 91 

Kapak 138 

Karite gum 47 

Kasai rubber 26, 27 

Kauri gum 162 

Kelgum 116 

Kempeff hard rubber substiiute.. 129 

Keratite 129 

Keratol 129 

Kerite 117 

Kermes 91 

Kiel compounds 129 

Kirrage compound 13S 

Koalatex 37 

Koener's devulcanizing process. 149 

Kommoid 117 

Koneman's devulcanizing process 149 

Komite 130 

Kremnitz white 175 

Kwilu rubber 27 

Kyanized cloth process 247 

La Belle's mineral rubber 139 

Lac 162 

Button 154 

Garnet 157 

Gum i6t 

Lace rubber 33 

Lactitis 130 

Lagos oil 217 

rubber 25 

Lahou rubber 24 

Lake Leopold rubber 26 

Lakes for coloring rubber 241 



Lallemantia oil 212 

Lamina fiber 130 

Lampblack, Analysis of 179 

for coloring rubber 178 

Lamu ball rubber 28 

Landolphia 8, 22 

Landolphia Thollonii 50 

Lanichol 212 

Lanolate, Aluminum 207 

Lanoline 212 

Lard oil 213 

Lavandula vera 215 

Lavender, Oil of 215 

Lead, Acetate of 79 

Black 83 

Blue 83 

Carbonate of 85 

Hyposulphite of 74 

Nitrate of 200 

Oxide of 96 

Oxychloride of 96 

Peroxide of 97 

Red loi 

Sublimed 102 

Sugar of 102, 204 

Sulphate of 102 

Sulphide of 58, 179 

Sulphurate of 71, 80 

White 104 

Leather impregnation, Belledin's 

process 134 

Leatherine 136 

Leatheroid 130 

Leatherubber compound 136 

Lemon, Oil of 215 

Leonard's compound 136 

Liberian rubber 24 

Liconite 117 

Ligroin 232 

Lime as a filler 91 

Carbonate of 85 

Chloride of 196 

Hydrochlorite of 198 

Hydrosulphuret of 198 

in coagulation 37 

Juice 2,7 

Oxalate of 201 

Phosphate of 97 

Quick 202 

Slaked loi 

Sulphate of 103 

Limeite 136 

Lini, Gum 161 

Linoxin 117 

Linseed oil 213 

Linum usitatissimum 213 

Liquid chlorine 75 



3o8 



INDEX 



Liquor of flint 200 

Litharge 92 

Lithargrite 93 

Litho-carbon 162 

Lithographic varnish 214 

Lithophone 93. "75 

Little known rubbers 41 

Liver of sulphur 75 

rubber 28 

Liverpool pressed rubber 22 

Loanda rubber 27 

Loango rubber 26 

Lombiro rubber 29 

Lomi rubber 25 

Lopori rubber 26 

Loranthus rubber 48 

Luft's celluloid rubber 136 

Lugo 118 

rubber 118 

Lump rubber 23 

Maboa gum 48 

Machacon juice 38 

Machine for testing air-brake 

hose 261 

Machine for testing vulcanized 

rubber 262 

Mackintosh manufacture 57 

Macwarrieballi gum 48 

Madagascar rubber 28 

Madanite , 136 

Madeira rubber 14 

Magnesia 93 

Maize oil 209 

Majunga rubber 28 

Malaya, rubber from 30 

Male rubber tree Si 

Manaos rubber 14 

Mandarva rubber 48 

Mangabeira rubber 19 

Manga-ice rubber 49 

Manganated linseed oil 214 

Manganese 94 

Peroxide of 97 

Mangegatu gum 48 

Manicoba rubber 19, 34 

Manila gum 163 

Manjack 163 

Manoh twist rubber 24 

Maponite 118 

Marble flour 94 

Marcy's (E. E.) rubber cure 

66, 67, 68 
Marks's (A. H.) devulcanizing 

patents 146, 149 

Marloid 130 

Massaranduba rubber 49 



Massisot 94 

Mastic 163 

Matto Grosso rubber 16 

Mayall's (Thomas J.) rubber 

cure 146 

Mayumba rubber 26 

Meal, Fossil 90 

Mechanical rubber goods manu- 
facture 53 

Menthol 163 

Metal, Fastening rubber to .... 251 

Metallined rubber 136 

Metals, action of rubber on .... 253 

Methane 232 

Mexican rubber 18, 34 

Meyer's vulcanizing process .... 69 

Mica 94 

Micanite 131 

Milk of sulphur 75 

Milling rubber 63 

Mimo-tannic acid 200 

Mimusops balata 298 

Mineral black 179 

India-rubber asphalt 163 

Orange 95 

rubbers 138 

tallow 163 

wax 164 

wool 95 

Minimum 95 

Mirbane oil 214 

Mitchell's (N. C.) rubber re- 
claiming patents 146 

Mixing rubber 61 

Moist heat tests of rubber substi- 
tutes 269 

Mold work 59 

Mollendo rubber 15 

Molybdenum blue 182 

Mongalla rubber 27 

Morat white 176 

Moroccoline 136 

Moudan white 176 

Mountain flour 95 

Mozambique rubber 27 

Mudar gum 49 

Mule gum 49 

Mulee (William) in the hard 

rubber industry 70 

Murac 298 

Muriate of ammonia 200 

Muriatic acid 200 

Murphy's (John) use of sulphur 

for gutta-percha 70 

devulcanizing process . . . 149 

Musa rubber 49 

Mustard oil 214 



INDEX 



309 



"M. R." 139 

Myrrh 164 

Nantusi 75 

Naphthaline 234 

Naphthas as solvents 232 

Natural pitch 164 

Neatsfoot oil 215 

Neen rubber 49 

Newbrough's (Dr. J. A.) vulcan- 
izing compound 68 

Newmastic 140 

Nicaragua rubber 17 

Nigeria, rubber from 25 

Niger rubbers 25 

Niggers (crude rubber), 

23, 24, 25, 27, 28 

Nigrite 131 

Nigrum elasticum 118 

Nipa fructicans ^7 

Nipa salt 27 

Nitrate of lead 200 

Nitric acid 200 

Nitrobenzine 215 

Nitro benzol 235 

Nitro-cellulose 141 

Notions in rubber 61 

Novelty rubber 118 

Nut-gall 200 

Nuts (crude rubber) 23 

Oak black 180 

Obach's (Dr. Eugene) classifica- 
tion of Gutta-percha 279, 293 
Chemical cleaning of Gut- 
ta-percha 282 

green Gutta-percha 283 

Ocher, Red 184 

Yellow 186 

Oil, Anhydrous paraffine 207 

Birch 207 

Bone 208 

Camphor 208 

Caoutchouc 208 

Castor 208 

Cod 209 

Cod-liver 209 

Colza 209 

Congo 217 

Consolidated 209 

Corn 209 

Cottonseed 209 

Creosote 210 

Dippel's 231 

Eucalyptus 210 

Fish 210 

Lagos 217 



Oil, Lallemantia 210 

Lard 213 

Linseed 213 

Maize 209 

Manganated linseed 214 

Mirbane 214 

Mustard 214 

Neatsfoot 215 

Olive 216 

Orizanum 216 

Palm 216 

Paraflfine 217 

Petroleum 217 

Poppyseed 219 

Rapeseed 219 

Resin 236 

Rock 217 

Rosin 219 

Russian mineral 219 

Shale 219 

substitutes analyzed 109 

Vulcanized 220 

Walnut 221 

White drying 221 

of amber 216 

lavender 215 

lemon 215 

orris 215 

peppermint 215 

rosemary 215 

tar 215 

thyme 216 

turpentine 235 

vitriol 201 

wormwood 216 

Oils, Blown 208 

Creosote 230 

used in rubber compounds 

and solutions 207 

Okonite 137 

Old Calabar rubber 25 

Oleargum 216 

Oleic acid 201 

Oleo resins 164 

Oleum succini 216 

white 176 

Olibanum, Gum 161 

Olive oil 216 

Orange ball rubber 28 

mineral 95 

vermilion 184 

Origanum oil 216 

Orinoco rubber 16 

Orpiment 187 

Orris, Oil of 215 

Orr's white 176 

Ossein 95 



310 



INDEX 



Oxalate of lime 201 

Oxalic acid 201 

Oxide of aluminum 95 

antimony 95 

gold 96 

iron, Red 184 

lead 96 

tin 96 

zinc 96, 176 

Oxolin 118 

Oxychloride of lead 96 

Oxydases in rubber 39 

Oysters (crude rubber) 23 

Ozocerine 165 

Ozocerite 164 

Ozonite 275 

Packing washers, Unvulcanized . 138 

Pagodite 96 

Paint, Prince's metallic 184 

TurnbuU's anti - fouling 

rubber 137 

Pala gum 49 

Palm oil 216 

Palo Amarillo 50 

Panama rubber 18 

Pantasote 131, 137 

Papovcr Somniferum 219 

Para rubber grades 13 

Shrinkage of 257 

Paraflfine 165 

oil 217 

Paragol 119 

Paris, Plaster of 98 

white 97 

Parkesine 119 

Parkes's cold cure 70 

formulas for dyeing rub- 
ber 239 

Parmelee's "hermizing" process. . 69 

Parthenium argentatum 20 

Paste rubbers 23, 25 

Payen's analysis of Gutta-percha 277 

Pedryoid 137 

Pegamoid 131 

Penang rubber 29 

Pensa's rubber 1 19 

Pentane 236 

Penta-sulphide of Antimony ... 75 

Penther's devulcanizing process. 150 

Peppermint, Oil of 215 

Perchoid 119 

Permanganate of Potash 201 

Pernambuco rubber 18 

Peroxide of hydrogen 201 

iron 184 

lead 97 



Peroxide of Manganese 97 

substitutes 119 

Peruvian rubber 15 

Peterson's devulcanizing process 150 

Petrifite 97 

Petrolatum 217 

Petroleum as a solvent 236 

Essence of 210 

jelly 217 

naphtha 233 

oil 217 

paraffine 217 

P. F. U 50 

Phenic acid 193 

Phosphate, Flour of 89 

of lime 97 

of soda 202 

Phosphoric acid 202 

Phosphorus 97 

Physical tests of vulcanized rub- 
ber 260 

Pickeum gum 50 

substitute 119 

Picradenia floribunda utilis 50 

Pigments for coloring rubber . . . 172 

Pink, Dutch 187 

Pipe clay 98 

Pitch 166 

Black 154 

Burgundy 154 

Coalite 156 

Natural 164 

Stearine 169 

Vegetable 171 

Pioneer mineral rubber 139 

Plantation rubber ;^;j 

Plaster of Paris 98 

Plasters, ingredients of 107 

Rubber 6r 

Plasticon 131 

Plastite 131 

Plumbagine 99 

Plumbago 99 

Pneumatic tire manufacture ... 57 

"Pongo" reclaimed rubber 112 

Pontianak 50 

Poppenhusen's (C.) use of rub- 
ber scrap 146 

Poppyseed oil 219 

Portland cement 99 

Potash 202 

Arsenate of 191 

Bichromate of 192 

Bisulphate of 192 

Caustic 195 

Permanganate of 201 

Potassium, Cyanide of 198 



INDEX 



311 



Potato celluloid 131 

Powder, Bleaching 192 

Powdered coal 99 

Pozelina 38 

Preservation of rubber goods . . 249 

Presspahm 131 

Price's (R. B.) devulcanizing 

processes ISO 

Prince's metallic paint 184 

Processes in coloring rubber ... 172 

Proofing business 57 

Fig juice 115 

Proto-Chloride of Sulphur 76 

Prussian blue 182 

red 185 

Pumice stone 100 

Puncture closer 140 

compound, Roland's .... 140 

fluids and fillers 139 

fluid, Frankenburg's 139 

fluid, Scott's 140 

Purcenite 120 

Purifying crude rubber 256 

Purple dyes for rubber 239 

Purub 38 

Purus rubber 14 

Puzzolana 100 

Pyrites, Iron 91 

Pyroxiline 142 

Pyroxylic acid 238 

Quick lime 202 

Quinn's rubber 120 

Rambong rubber 34 

Rangoon rubber 29 

Rapeseed oil 219 

Rathite 137 

Raymond's vulcanization mixture 77 

Reclaimed rubber 143 

Reclaiming processes 145 

salt 202 

Red chalk 100 

hematite 184 

Indian 184 

lead loi 

ocher 184 

oxide of iron 184 

pigments 183 

Prussian , 185 

Venetian 184 

Reinhardt's analysis of rubber . . 270 

Remanso rubber 19 

Rennet 202 

Resin, Adamanta 151 

oil 236 

Sludge oil 170 



Resinolines 120 

Resins contained in rubber 223 

in rubber compounding 

151, i66 

Oleo 164 

Retin asphalt 167 

Retinite 167 

Rhea-gum 120 

Rhigolene 237 

Rice rubber 121 

Richard's (Albert C.) rubber 

cure 67 

Rider (John) on gutta-percha 

vulcanization 70 

Roland's puncture compound ... 140 

Root rubber 50 

Rosaline 121 

Rosemary, Oil of 215 

Rosin 167 

oil 219 

Ross's white 177 

Rotten stone loi 

Rouen white 177 

Rubberaid 121 

Rubberic 137 

Rubberite 121, 140 

Rubber asphalte 137 

flux 122 

milk, Artificial 254 

Velvet 137 

Ruberine 121 

Ruberoid 121 

Russian mineral oil 219 

Russian substitute 122 

Dankwerth's 113 

Sal Ammoniac 203 

Saleratus 203 

Salicylic acid 203 

Sal soda 203 

Salt 203 

in coagulation 38 

Nipa 37 

Reclaiming 202 

Saltpeter 203 

Saltpond rubber 25 

Sandarc 168 

Sankuru 26 

Santos rubber 19 

Sapium biglandulosum 51 

Sarco 139 

Sarua rubber So 

Sausage (crude rubber) 27 

Sawdust as a filler 106 

Saxon blue 182 

green 188 

Scott's puncture fluid 140 



312 



INDEX 



Scrap rubber 34 

Seedlac 168 

Selenium 68, 70, loi 

Seringuina 38 

Sernamby (Para) rubber 13 

Shale oil 219 

spirit 237 

Shellac 168 

Shrinkage of rubber 256 

Sieba gum 51 

Siemens (Dr. Werner von), pio- 
neer in gutta-percha 285 

Sierra Leone rubber 24 

Silex loi 

Silica loi 

Silicate, cotton lOi 

of soda 203 

Silicon, Fluoride of 198 

Simond's devulcanizing process. 146 
Simpson's (E. L.) rubber cure.. 68 

Sinapsis nigra 214 

Size 169 

Slag wool loi 

Slaked lime loi 

Slate 102 

Sludge 220 

oil resin 170 

Smalts 181 

Smith (Willoughby) on Gutta- 
percha 133 

Smoking rubber 35 

Soap in coagulation 38 

Substitutes 122 

Soaps 203 

Soapstone 102 

Soda 204 

Biborate of 192 

Carbonate of 194 

Caustic 194 

Crystals of 198 

Phosphate of 202 

Silicate of , 203 

Sulphate of 204 

Tungstate of 206 

Sodium, Chloride of 196 

hyposulphite 204 

Solicum 122 

Solubility of India-rubber 222 

Soluble glass 204 

Sorel's compound 131 

Spanish white 177 

Specific gravity of rubber 259 

Spence (David) on Oxydases.. 39 

Spermaceti 170 

Spirit, Shale 237 

Wood 238 

Spirits of turpentine 237 



Spirits of Wine in coagulation 38 

Sponge, Rubber 255 

Spruce gum 169 

Stabilit 131 

Stamp rubber 60 

Starch 102 

Stationers' rubber goods 55 

Stearic acid 204 

Stearine 169, 220 

pitch 169 

Stibnite 102 

Sticklac 168, 170 

Sticks (crude rubber) 28 

Stockholm tar 170 

Stone, Pumice 100 

Rotten loi 

Storax, Balsam of 152 

Straits rubber 32 

Strips (crude rubber) 23 

Suber's filler 140 

Sublimed lead 102 

Substitute, Amber-resin iii 

Bisulphide of carbon 227 

Black German iii 

Brown's 127 

Chicle 112 

Chinese wood oil 112 

Corn oil 113 

Dankwerth's Russian 113 

De Pont 127 

Fayolles' 114 

Franklin 115 

Griscom's 115 

Gutta-percha 116 

Harmer's 134 

Jones's 116 

Kempeff hard rubber 129 

Leonard's 136 

Pickeum 119 

Russian 122 

Tetrachlormethene benzine 237 

Tong oil 123 

Wickmann's 124 

Substitutes, Analysis of oil .... 109 

rubber 268 

Peroxide 119 

Soap 122 

for Gutta-percha 108, 125 

hard rubber 125 

India-rubber 108 

Succini, Oleum 216 

Sugar of leaA 102, 204 

Sulo 122 

Sulphate of alumina 204 

copper 204 

lead 102 

lime 103 



INDEX 



313 



Sulphate of soda 204 

zinc 103 

Sulphide, Barium 72 

antimony, Crimson 184 

lead 76, 179 

uranium 180 

zinc 76, 177 

Sulphur 76 

Amorphous 71 

Balsam of 76, IS3 

Chloride of . .T 73 

fumes in coagulation 38 

Honeycomb 74 

in rubber substitutes 269 

Liver of 75 

lotum 76 

Milk of 75 

Proto-chloride of 76 

Sulphuret of antimony Golden.. 73 

lead, artificial 71, 80 

Sulphuric acid . . , 205 

Surgical rubber goods 55 

Susu-poko gum 51 

Synthetic rubber 40 

Tabbyite 139 

Tdbern(Bmontana Thursioni 51 

Taking rubber 51 

Talc, French 103 

Talite 103 

Tallow 220 

Mineral 163 

Talotalo gum 51 

Tamatave rubber 28 

Tannic acid 205 

Tannin 205 

Tar 170 

Birch-bark i53 

Candle I54 

Coal 156 

Oil of 215 

Stockholm 170 

Tartar, Cream of 198 

Tartaric acid 206 

Tava rubber 27 

Terra-verte 187 

Terry (H. L.) on specific gravity 

of rubber 259 

Tetrachloride, Carbon 228, 237 

Tetrachlormethene benzine sub- 
stitute 237 

Texoderm 142 

Textiloid 122 

Theilgaard's (Albert) devulcan- 

izing process 150 

Thenard's blue 182 

Thermophoric mixture 255 



Theskelon cement I37 

Thimble rubbers 22 

Thion 237 

Thomas's (James) rubber cure.. 67 
Thomson (Sir William) on ef- 
fect of metals on rubber. 253 

Thus, Gum 162 

Thyme, Oil of 216 

Tin, Oxide of 96 

Tire life 140 

Tire manufacture 57 

Tires, Pneumatic, Testing of . . . 261 

Tirucalli gum 51 

Tobago rubber 34 

Togoland, rubber from 25 

Tolu balsam 170 

Toluene 237 

Tong oil substitute 123 

Tongues (crude rubber) 23 

Torres coagulation system 38 

Torrey's (Joseph) method of 

determining rubber 272 

Touchpong gum 51 

Tragacanth, Gum 161 

Tragasol, (jum 161 

Tremenol 123 

Trinidad asphalt 170 

rubber 34 

Tripoli 103 

Trotter's (Jonathan), \Tilcanizing 

process 66 

Troye's white I77 

Tungstate of ammonia 206 

soda 206 

Tungstic acid 206 

Tuno gum 51 

Turpentine 171, 220 

Gum 162 

Oil of 235 

rubber 123 

Spirits of 237 

TurnbuU's anti- fouling rubber. . . 137 

Tuxpam strip rubber 18 

Twists (crude rubber) 23, 24 



Uele rubber 26 

Uganda rubber 27, 35 

Ultramarine, Blue 180 

Green 188 

Umber 185 

Burnt 84 

Unusual ingredients in dry mix- 
ing 105 

Upper Congo rubber 26 

Upriver Para rubber 14 

Uranium, Sulphide of 180 



314 



INDEX 



Valves, Preservation of rubber 

in 250 

Van den Kerckhove's (G.) rub- 
ber smoking apparaus ... 37 
Vapor process of rubber cure... 253 

Varnish, Lithographic 214 

Vaseline 220 

Vegetable charcoal 86 

Vegetable pitch 171 

Vegetaline 132 

Velvril 123 

Venetian red 184 

Venice turpentine 235 

Vermilion 183 

Orange 184 

Vesuvian white 77 

Virgen rubber 18 

Virgin rubber 18 

Viscoid 132 

Viscose 132 

Vitriol, Oil of 201 

Vitrite 132 

Volenite 124 

Voltax 138 

Voltit 123 

Vorite 124 

Vulcabeston 132 

Vulcanina 138 

Vulcanine 77, 138 

Vulcanization of Gutta-percha.. 289 

India-rubber 65 

pressures 78 

temperatures 78 

Vulcanized fiber 132 

oil 220 

rubber, Analyses of 260 

Vulcanizing ingredients and pro- 
cesses 65 

Vulcole 77 

Vulcoleine 238 

Walnut oil 221 

Wamba rubber 27 

Washers, Unvulcanized packing 138 

Washing rubber 61 

Waterproof fabric, A porous . . 247 

glue 124 

Watertown, Mass., Tests of rub- 
ber goods at 262 

Wax, Carnauba 155 

Earth 156 

Japan 212 

Mineral 164 

Waxes in rubber compounds ... 151 
Weber (Carl Otto) on analyses 

of rubber 267, 270 

on resins in rubber 223 



Weber's cellulose compound . . . 142 

West Indian rubber 18 

Whalebone, Artificial 125 

Whaleite 138 

Wheat flour 103 

rubber 124 

White, Barium 174 

Beckton 174 

Bougival 174 

Calamine 175 

Calcium 84 

Charlton 175 

colors for rubber 174 

Fard's Spanish 175 

Fulton 175 

Griffith's 175 

Kremnitz 175 

lead 104 

Morat 176 

Moudan 176 

Oleum 176 

Orr's 176 

Paris 97 

Ross's 177 

Rouen 177 

Spanish 177 

Troye's 177 

Zinc 178 

Whiting 104 

Wichmann's substitute 124 

Wilhoft's (Dr. F.) vulcanizing 

process 71 

Willman's (Andreas) rubber 

cure 68 

Winthrop gum 124 

Wolf ert 124 

Woodite 138 

Wood oil substitute, Chinese ... 112 

Wood spirit 238 

Wool, Mineral 95 

Slag 101 

Worm rubber 33 

Wormwood, Oil of 216 

Wray's (Leonard) compound . . 133 

Xanthorrhea gum 171 

Xelton 133 

Xingu rubber 14 

X-rays for analyzing Gutta- 
percha 285 

Xyloidin 171 

Xylol 238 

Xylonite 142, 171 

Yale blue 181 

Yellow, Arsenic 186 

Aureolian 186 



INDEX 



315 



Yellow, Barberry 186 

Cadmium . . , 185 

Chrome 187 

Gamboge 182 

gutta 52 

ocher 186 

pigments 185 

Zackingummi 125 



Zinc, Borate of 174 

Carbonate of 175 

Chloride of 197 

Iodide of 199 

Oxide of 96, 176 

Sulphate of 103 

Sulphide of 76, 177 

white 178 

Zinsser's barrel lining 138 

Zuhl's devulcanizing process . . . 150 



ADVERTISEMENTS 



AD J \ERTISEMENTS. 




W-Pe^' 



PUBLISHED ON THE 1st OF EACH MONTH BY 

The India Rubber Publishing Company 

No. 395 BROADWAY, NEW YORK 

Edited by 
HENRY C. PEARSON 



ESTABLISHED in 1889, to represent the interests of the manufactur- 
ers and distributors of India-rubber and allied goods in the United 
States, this journal has broadened its scope until it now commands a 
position of importance as a record of the rubber trade and industry in all 
other countries as well. At the same time it has taken a leading position 
as an exponent of the rubber planting interests and the intelligent exploita- 
tion of forest rubber, while its statistical department is more fully relied 
upon than any other source of information of this class. 

The publishers believe that to-day no other special journal published 
covers its field so fully, or commands a circulation so widespread or of such 
a high character. The contents of The India Rubber World are, for 
the most part, expert information, covering whatever is new in factory pro- 
cesses, in applications of rubber, in company development or changes, mar- 
ket conditions, and whatever else may concern the entire field of rubber in- 
terests. 

As) an advertising medium, it is believed that the paper occupies an 
exceptionally high position as a medium for bringing manufacturers and 
consumers of rubber goods in contact, and for attracting the attention of 
manufacturers to new appliances and materials. 



YEARLY SUBSCRIPTION: 

UNITED STATES AND MEXICO, .... 
ALL OTHER COUNTRIES, ..... 



$3.00 
3.50 



THE INDIA RUBBER PUBLISHING CO, 

395 BROADWAY, NEW YORK 



ADVERTISEMENTS. 




Laboratory Washer — For use on small 
samples ranging from 1 to 5 Pounds. 
Same general description as No. 2 Washer. 



THE 



Turner yaughn& Taylor C2 

Cuyahoga Falls, Ohio, U.S.A. 




Water Separator — Removes 60 to 65 per 
cent, of moisture from reclaimed stock. An 
invaluable machine for drying mechanically. 



.^DI'ERTISEMENTS. 



F. H. APPLETON & SON 




Manufacturers of I^ECLAIMED RUBBER 



FACTORY : 

Franklin, Mass. 



BOSTON, MASS. 



Telephone: OXFORD, 460 



OFFICE: 

1 86 Summer St. 

Boston 



CABOT'S 

RUBBER BLACK 

For more than twenty-five years we have 
made a specialty of producing absolutely 
pure lamp-blacks for rubber manufacture. 
Our blacks are strong in coloring power, 
rich and intense in tone, and contain no 
grease, grit or other impurities. 

BENZOL 

The Most Powerful Solvent for Rubber. 

At present prices Benzol is the cheapest 
solvent for the rubber factory, as it is far 
more efficient than any other. 

Samples and prices on request. 

SAMUEL CABOT, Inc. 

Manufacturing Chemists 
BOSTON, - - - MASSACHUSETTS 



ADVERTISEMENTS. 



OHM LAC-- 

HYDRO-CARBON COMPOUNDS 

PUT UP IN DIFFERENT CONSISTENCIES TO SUIT THE 
NEEDS OF MANUFACTURERS IN VARIOUS COMPOUNDS 



THE COMPANY HAS AN EXPERT IN RUBBER MANUFACTURING, AND IS IN A 

POSITION TO GIVE INTELLIGENT INFORMATION PERTAINING TO THE USE OF 

HYDRO-CARBON IN ALL CLASSES OF RUBBER COMPOUNDS 

THE COMPANY ALSO MAKE A COMPLETE LINE OF INSULATING COMPOUNDS 

FOR PAINTS, WIRES, COIL SATURATING, POT HEADS, CABLE JOINTS, ETC., 

AND A FULL AND COMPLETE LINE OF BLACK PAINTS AND JAPANS. 



OHM LAC MFG. CO. 

OFFICE: 1101 MONADNOCK BLDG., - CHICAGO 
FACTORY: CLEARING, - - - - ILLINOIS 



WRITE FOR SAMPLES 



Since 1900 

no substitutes like 

THE 

STAMFORD 

SUBSTITUTES 



IDEAL 

PRODUCT 

OF AN 

IDEAL FACTORY 



The Oldest American Producers of hath 
the White and the T>ark Grades of 

RUBBER SUBSTITUTES 



rlD VERTISEMENTS. 



ESTABLISHED 1844 



A. SCHRADER'S SON, INC. 

28-30-32 ROSE STREET, NEW YORK CITY 

MANUFACTURERS OF 

SCHRADER UNIVERSAL VALVES 

FOR PNEUMATIC TIRES 



Schrader's Stopple and Combination Syringe Connection for Hot Water Bottles 

Schrader's Pillow Valves for Pillows, Life Preservers and similar articles 

Hose Couplings, Contracted Ferrules for Garden Hose 

Bands and Fittings 

Shower Bath Sprinklers Shower Rings 

Brass Fittings for Rubber Goods of Every Description 



DIVING APPARATUS 

Furnishers of Diving Apparatus to United States Navy. 
Awarded Medal at Jamestown Exposition, 1907. 



Rubber, Gutta,iBalata Machinery 



In all its 
Branches 



FOR FACTORY AND PLANTATION 
BRIDGES 



HEvwooo* PATENT FRICTION CLUTCHES 



Catalogues in English, French and German 

DAVID BRIDGE CO., PEAR WORKS 

CASTLETON, MANCHESTER, ENGLAND. 



LITHOPONE 

SULPHATE OF BARYTES 

CARBONATES OF BARYTES 
SULPHATE OF LIME 

OXIDE OF ZINC 

ALL IMPORTED 



GABRIEL & SCHALL 

205 PEARL STREET, NEW YORK 



ADVERTISEMENTS. 


















\ BOOK m RUBBER PLANTERS 

By the Editor of The India Rubber World 

The Home and Colonial Mail (London) says : "When Mr. Henry C. 
Pearson started out to study rubber culture in the tropics, and to record 
his impressions, he did his work thoroughly." 

The South American Journal says : " From the view of the rubber 
planter, and the investor in the rubber plantations, the book is of the 
greatest interest, showing comparisons of growth, methods of tapping, 
and preparation in various countries. " 

Price, $3.00 Prepaid 



The India Rubber Publishing Co. 

No. 395 Broadway - - NEW YORK 



AD J ^ERTISEMENTS. 



FIINEST QUALITY 

QUAYULE 

Made from strictly fresh shrub 




BRAND 
QUARAINTEED ALWAVS THE SA.1VIE 



The same quality, washed and dried, ready for use is offered 
in our 




BRAND 

If you cannot obtain results from Crude Guayule, try 
Durango. 



EDWARD MAURER 



97 Water Street, 



NEW YORK 



A D VER TIS EM EX TS. 



BIRMINGHAM IRON FOUNDRY 



Established 1836 



DERBY, CONN. 



Incorporated 1850 




"BIRMINGHAM" RUBBER MILL MACHINERY 

Two, three and four-Roll Standard Chilled Roll Calenders — Pearce Patent 
six-Roll Double Friction Calender — Pearce Patent eight-Roll Double Sheet- 
ing Calender— Embossing Calenders for Carriage Cloth — Experimental 
Calenders — Soling and Upper Calenders — Engraved Steel Rolls, etc., etc. 

WASHERS 

Standard two-Roll Washers, from 83^^^xl2^^ to 18''x40'''— three-Roll 
Washers — Washing Plants arranged with overhead Drive — Washers Equip- 
ped with Self- Adjusting Guides and Safety Stops — Double Geared Crackers. 

MIUUS 

Standard Mills with Chilled or Sand Rolls 6'', W\ W, 12^ 14^ W, 
1&\ 18'''', 20^'', 22"'' and 24'' in diameter, any length— Double Geared Refiners 
— Experimental Mills — Mills equipped with Self-Adjusting Guides, Safety 
Stops, Water-Cooled Boxes, etc. , etc. New Designs and Patterns throughout. 

PRESSES 

Belt Presses, 30'', 42", 50", 52", 60" and 74" in width, 30 feet and under 
in length — Clark's Hydraulic Stretcher— Square Presses, any number of 
Platens, 12", 18", 24", 30", 36", 40", 48", 52", 60" and 74"-Heel Presses- 
Screw Presses— Accumulators and Pumps. 

SPECIAL MACHIINES 

Hose making Machines — Special Machines for Air-Brake Hose — Belt 
Making Machines — Bias Cutting Machines for all Purposes— Spreaders — 
Duck Slitting Machines — Band Cutters, Vulcanizers, etc., etc. 

SMARXIIVa, QEARIISQ, Etc. 

Hammered Steel Shafting — Machine Molded and Cut Gearing — Friction 
Clutches — Couplings— Motor Drives— Rope Drives — Pulleys— Pillow Blocks 
—AH parts needed in alterations or repairs. 



AD J ^ERTISEMENTS. 



TYPRE <a RING, Ltd., 

IG Mincing Lane, LONDON, E. C. 

[From a report on the International Rubber and Allied Trades Exhibition, in 
London, from T/ie Itidia-Rubber Jojinial.'] 




TYPKE & KING'S DISPLAY 
International Rubber Exhibition at London 



The exhibit of this company was one of 
the features of the Exhibition, the arrange- 
ment of the stand and show cases was unique, 
and called forth commendations from all 
who inspected the display. 

For more than twenty-five years the firm 
has made a special study of the requirements 
of the rubber trade. Its large works are at 
Mitcham Common, Surrey, and Rainham, 
Essex, and the company now has agents in 
Manchester, Birmingham, Edinburgh, Bel- 
gium, France, Germany, United States, Rus- 
sia, Canada, and Japan. 

Of the articles exhibited we noticed par- 
ticularly the golden and crimson antimonies, 
ssveral shades of the latter being shown; 
the outstanding feature of this company's 
antimonies is that the percentage of free sul- 
phur is always the same, and the user is 
therefore able to obtain regular results. Sam- 
jjles of rubber sheet, bat handles, tubing, etc., 
were on view, actually made from these an- 
timonies, and were pronounced to be very 
fine indeed. 

A good collection of india-rubber substitutes 
was made by the company. Of the white 
there were the special for mixing for proof- 
ing purposes, a quality which has been in use for very many years and has always given 
uniform results, and the ordinary white substitutes, S.O. and S.O.O., for mechanical 
goods, tubing, sheeting, etc. There were also white and black snow sorts; the last-named 
is made by this company alone,-. and is intended for mixing with rubber for the manufac- 
ture of cut sheet. A new kind of dark substitute, to which the company has given 
the name "Parateka," was also shown; this is reputed to be the lightest on the market, 
having a specific gravity of 0.9642. 

There were also coloring substitutes in red, orange and yellow shades for heightening 
the color of rubber goods. They were pronounced quite free from acid. 

Black hypo and special black pigment, specially prepared for mechanical and piece goods 
respectively, were also displayed. These are always uniform in composition and percentage 
of free sulphur. 

The firm showed a fine set of tennis shoe soles in yellow, blue, green, red and black, 
made with their colors, which were greatly admired. The same shades are also made for 
enamel work. 

The special grades of vegetable black are very fine; the "Extra" is an intense black, 
very light, and can be used in small proportions. 

Finest pure sulphur is another specialty; being perfectly neutral it is suitable for rubber 
work. 

Zinc sulphide was shown in white and yellow shades; the company have a new quality 
of white testing 98 per cent, that is of very fine texture. 

Among other articles exhibited were vermilion, of various shades; pure fine lime, 
plumbagine for oil resisting valves; scarlet stain for cheap red goods; carbon tetrachloride, 
absolutely uninflammable; precipitated chalk very fine, white and light; barytes, French 
chalk, lithopone, calcined magnesia, carbonate of magnesia, pure precipitated sulphur, 
sublimed lead, and zinc oxides in all qualities. 



AD VERTISEMENTS. 



Parrel Foundry & Machine Co 

ANSONIA, CONN., U.S.A. 



MANUFACTURERS OF THE 



(( 



FARREL " RUBBER MACHINERY 




EXPERIMENTAL CALENDER AND GRINDER 



CALENDERS, WASHERS, GRINDERS, 
HYDRAULIC PRESSES, ETC., FOR ALL 

RUBBER MANUFACTURING 



DESIGNERS AND BUILDERS OF COMPLETE MECH- 
ANICAL, SHOE, HOSE, HARD RUBBER AND 
RECLAIMING PLANTS. 

CHILLED IRON, DRY SAND AND STEEL ROLLS. 

COIL FRICTION CLUTCHES (PAT.) AND POWER 
TRANSMISSIONS. 



ADlliRTlSEMENTS. 



ACID PROOF NO PITCH 

ALKALINE PROOF NO TAR 

ELECTROLYSIS PROOF NO ASPHALTUM 

KAPAK 

Pure Natural Hydrocarbon, Elastic, Resilient, used extensively in 
Mechanical Rubber Goods, Insulation and Hard Rubber. 



RAVEM MINING CO. 

Marquette Building 

CHICAGO 



♦ ♦ ♦ ♦ ♦-♦-♦^ ♦ ♦ ♦ »< 



i Dixon'» riake Qra|)hite 

♦ To get the full value to be derived from the use of graphite you should t 

T employ only Dixon's Flake Gra|)hite which has proven its value. It is the t 

4 preferred form of graphite for all lubricating requirements, and is used as I 

t well in the manufacture of packings and other supplies in which graphite t 

I is used to advantage. ^ 

i Write for further inform/xtion and samples I 

JOSEPH DIXON CRUCIBLE CO., \ 

I JERSEY CITY, N. J. I 



The S. p. WETHERILL COMPANY'S 

No. 600 RED OXIDE 

Has GREATER COLORING CAPACITY than any other 

Red Pigment. 

925 Chestnut Street, Philadelphia 



AD VERTISEMENTS. 



RICHER 

BRAINDS OR 

SUBLIMED WHITE LEAD 

(Non-Poisonous) 

SUBLIMED BLUE LEAD 
RUBBER MAKERS^ LITHARGE 

are standards of excellence and efficiency. 
We shall be pleased to quote delivered prices 
anywhere in the United States and abroad. 
We maintain warehouses in all prin- 
cipal cities, which insure prompt service. 



Address inquiries to— 

RICHER LEAD COMPANY 

TACOMA BUILDING, CHICAGO; 
and 100 WILLIAM STREET, NEW YORK. 



Works: JOPL^IIN, MISSOURI, U^S.A, 



Richer Lead Company 



ADVERTISEMEXTS. 



ALUMINITE 

THE NEW FILLER FOR 
RUBBER COMPOUNDS 



ABSOLUTELY INERT IN CHARACTER 



Low Specific Gravity, 2.63 



LARGE PERCENTAGE MAY BE USED. 

DISPLACES ZINC, LITHOPONE, BARYTES, FLAKE, &c 
CHEMISTS INDORSE IT. 



ESPECIALLY ADAPTED FOR ALL MECHANICAL AND 
MOLDED GOODS. 



TEST SAMPLES SENT ON APPLICATION. 



The Cawn Mining & ig. Co. 

CANTON, OHIO, U.S.A. 



AD VER TISEMBNTS 



A Book for Everybody Who 
Has to Do With Rubber 
Tires for Business or Pleasure 



The newest, and we should say the most 
complete, work dealing with the subject of 
rubber tires.— T/ie Canadian Motor, Toronto. 

Deals with the rubber tire of every kind, 
and from every possible point of view. — The 
Automobile, New York. 

The author has well succeeded in the 
task. His book is an authoritative source of 
information in this branch of manufacture, 
and is to be complimented for its accuracy. — 
Gummi-Zeitung, Dresden, Germany. 

Even the best informed will learn some- 
thing from it, and to the average man with an 
interest in tires who once gets hold of it, it 
will become an inseparable companion. — The 
India-Rubber Journal, London. 

There may be those who think they know 
all about tires that is worth while, but they 
will conclude differently if they will peruse 
this well-written volume. — Carriage Monthly, 
Philadelphia. 

Mr. Pearson [the author] is a practical 
expert in matters pertaining to rubber, and 
has since the very inception of the pneumatic 

tire industry and trade been in very close touch with that line. — Das Radmarkt, 

Bielefeld, Germany. 

Deserves the greatest attention from the rubber trade. — Le Caoutchouc 
et la Gutta-Percha, Paris. 

Price, $3,00 per Copy Prepaid 




THE INDIA RUBBER PUBLISHING 
=^=^= — = COMPANY =— — = 



Number 395 Broadway 



New York 



i6 ADVERTISEMENTS. 



\ THE CARTER BELL MFG. CO. I 

150 Nassau Street, 
New York. 

Manufacturers 

of I 

High Grade | 

RUBBER SUBSTITUTES I 

and t 

Chemical Products | 

For Soft and Hard Rubber Compounds | 

White 

Rubber 

Substitute 

SOLID AND POWDERED 



T. C. ASHLEY & CO. 

683 Atlantic Avenue - - - BOSTON 



ADVERTISEMENTS. 



Address for letters and telegrams : Maschinenbau Golzern 
Mulde (Germany) 



UASCniN[NBAy - AKTI[NG[8[LL8Cniin 

GOLZ[RN-GRIMMi\ 

GOLZERN - - - SAXONY 

MAKERS OF ALL KINDS OF 

MACHINERY 



— FOR THE MANUFACTURE OF 



India Rubber vulcanizing Pans 

Hard Rubber (Ebonite) drauiic vulcanizing 

Presses 

uuttapercha 

* Hose and Block Ma- 

Celluloid ^•^'""y 

. J f-«i Clutches of every 

Crushing Vulcanized Fiber description 

r;:^ Asbestos 

Grinding Machines p^^^^^ j^^^^^ 

Calenders 

Dough Mills Balata Belting 

Cutting Machines 
Spreading Machines ExplOSive Material 



AD VRR T IS EM EN TS. 



ROBT. E. TYSON THOS. H. TYSON 

TYSON BROTHERS 

MANUFACTURERS OF 

RUBBER 
SUBSTITUTES 

Quality Guaranteed 

WHITE and BROWN RAPE 
ALL GRADES OF BLACK 

Warranted Free from Acid or Alkali, AND WILL 
NOT BLOW UNDER CURE 



PRICES CONSISTENT WITH QUALITY 



Samples and analysis of same cheerfully furnished upon request 



FACTORY AND 
OFFICE: 



STAMFORD, CONN. 



A OVER TISEMENTS 




RUBBER TRADE 

DIRECTORY 



^ The First American Directory ^ 

^ of Rubber Factories and Distributing ^ 

^Houses; Every State Covered.^. 



^ It contains nearly 300 Large ^ 

^, Pages (9x6 inches), is Conveniently ^ 

^ Arranged, and Neatly got up. ^ 



Price $3, Post Paid 



Published at the Offices of 

THE INDIA RUBBER WORLD 

No. 395 BROADWAY 
NEW YORK 



AD VER TI SEME NTS 



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|. •••*•>•••••. •»***1 






ARIAU BRANDS 

Rubber Substitute, Displacers and Chloride of Sulphur 

Made from Best Materials and by Up-to-Date Methods 

White Substitute, Black or Brown Substitute, Chloride of Sulphur, Scarrite, 
High-grade Hydro-Carbon, Bi-Sulphide of Carbon, Tetrachloride of Carbon. 

IMPORTERS 

Asphalts, Pitch, Cements, Earths, Chemicals, Dryers, Dry Colors, Lime, 
Varnish and Other Gums, Oils, Acids, Rosin, Pigments, Shellac, Waxes, 
and Sundries. 

WIUUIAM H. SCHEEU 

159 Maiden Lane and 37 Fletcher Street, NEW YORK, N.Y. 




The International Rubber 
AND Allied Trades Exhibition 

HELD AT OLYMPIA, LONDON, 1N1908 

PROVED SUCH A SUCCESS THAT A REPETITION OF 
IT, TO BE HELD THREE YEARS LATER, WAS AT 
ONCE DETERMINED UPON, THE ORGANIZING 
MANAGEMENT TO BE IN THE SAME HANDS AS THE 
FIRST EXHIBITION : : : : : 

1^^ The organizing manager of the Olympia Rubber 

Show Avas: 

A. STAINES MANDERS, 
75 Chancery Lane, - - LONDON, W.C. 



MAY 13 



The Aluminum Flake Company 

Miners and I^efiners of 
ALUMINUM FLAKE 

AN ORIGINAL PIGMENT, SUITED TO ALL LINES OF 

RUBBER WORK 

Physical condition a chemical combination by nature 

Base, Metallic Aluminum 

Gravity, 2.58 

Absolutely inert 

It toughens Rubber, gives it life and lightens gravity 

Over 7,000,000 pounds sold and contracted for in two years 



THE ALUMINUM FLAKE COMPANY, Akron, 0. 

FREDERICK J. MAYWALD, F.C.S. 
Consulting Chemist and Expert 



Remedying Defects in Processes. Improving 
and Inventing Processes. Improving Quality 
and Yield of Products. Testing and Report- 
ing on New Processes. W^orking out Manu- 
facturing Formulas. Utilizing Wastes and 
Unapplied Substances. Softening and Clarify- 
ing "Water. Reducing' Manufacturing Costs. 
Experimental Tests and Investigations. J- ^ 



TESTING OF RUBBER MANUFACTURERS' SUPPLIES A SPECIALTY 



89 Pine Street, NEW YORK 



TELEPHONE 823 ••JOHN' 



HIDROGiRBON 

Why our "MALTHA BRAND " IS BEST 

1 . Will retain its flexibility at zero weather. 

2. It will not soften and run all over your compound room on the hottest 
day in summer. 

3. Being semi-elastic it can be cut with a knife which overcomes the harm 
done by brittle Hydro-Carbons that have to be broken up with an axe, 
causing specks to fly in all directions, sometimes falling into white or red com- 
pounding ingredients, or into batches of the same that have been already 
weighed up ready for milling. 

4. It is pure and runs uniform in quality, something a Hydro-Carbon 
mixed with Gilsonite Does Not, because Gilsonite varies so in chemical 
consistency, especially in sulphuric contents. 

5. You can use hot mill rolls in mixing up a compound containing our 
"Maltha" Hydro-Carbon, and instead of sticking to the rolls, as other mixed 
Hydro-Carbons do, it is readily absorbed by the compound, greatly aiding the 
rapid assimilation of the mineral pigments. 

6. Its fluid point is such that it forms a homogeneous blend in vulcaniz- 
ing, and overcoming the harsh effects of the minerals used in the compound. 

7. Being pure it will not itself oxidize, and rubber goods into which it 
is incorporated resist oxidization much longer than the same compound 
without it. 

8. Its use helps to get a smooth, fine-grained result in calendering. 

9. While " Quality" is our motto, the price is low. 

10. "A customer once a customer always ": is not this an argument 
which warrants your giving it a trial ? 

We will be pleased to furnish a working sample FREE. Drop us a 
line now. 

AMERICAN WAX COMPANY 

BOSTON, MASS., U.S.A. 



